What do you do when you are too rich to work but too young to retire? If you made your millions from Microsoft share options, chances are you have started your own charitable foundation. Or if you are the eighth richest man in the world, you commission the world's hippest architect to create a shrine to Jimi Hendrix. Ann Treneman meets Seattle's new Medici
Paul Allen is the eighth richest man in the world and gives millions away every year to hospitals, universities, children's programmes and the like, especially in his home-town of Seattle. And he owns the local major-league football team. So far, so good. But there is another side to Paul Allen that is a little more dangerous. The bearish Microsoft co- founder is a Hendrix freak. In fact, he could be the world's biggest Hendrix freak and he is certainly the richest. The boy who played air guitar to "Purple Haze" is now 44 and worth $14 billion. He has long been able to afford to buy Hendrix's real guitars (or what is left of them after being smashed, set on fire and stomped on), and other Jimibilia. When the collection grew to tens of thousands of items, he began to wonder what to do with it.

He thought about putting it on display for all to see. Why not give it as a present to Seattle? It's the kind of thing that this city is getting used to, as a growing number of instant millionaire Microsofties (as they call themselves) have decided to "retire" and give something back to the community. They are being called the digirati, the geekocracy, the techno- millionaires and their passions are being labelled as hi-tech philanthropy. But it is more than that. There is a tremendous amount of money and determination floating around Seattle. Bill Gates and Paul Allen could end up being seen as the Medicis of our times and this Pacific Rim city seen as their 21st-century Florence. And this explosion in arts and culture will also include technology and education, because the New Philanthropists are young, energetic and want to do more than just write cheques.

"We are so different from the traditional philanthropist who writes the million-dollar cheque and wants his name on a building," says millionaire and former Softie Tina Podlodowski. "We, too, might write that cheque but we are not going to do it before we've spent five years in the organisation and understand the goals and how it runs. We are sort of the worst nightmare for a non-profit board, but their best friend, too, because we make them do that sort of business planning!"

Ms Podlodowski is now a Seattle city councilwoman and has used her skills to raise millions for various causes. In her office with its stunning mid-skyscraper view, she drops a few names. There is Bill (no last name needed around here), who is in a class of his own with his latest donation of $200 million to get America's libraries on-line. There is Scott Oki, who has become something of a non-profit guru to Microsofties and who now sits on 20 non-profit boards. Ida Cole personally saved the city's historic Paramount theatre. Trish Millines has vowed to change the lives of thousands of poor children of colour who might otherwise end up flipping burgers at McDonald's.

Paul Allen's name comes up a lot. The man who left Bill to get on with it in 1983 gives big and lives big. He owns a Boeing 757 and his purchase of the Seattle Seahawks football team cost a cool $200 million. Podlodowski ticks off a list of good works, but her eyes really start to sparkle when the subject turns to his Hendrix fixation. "Have you seen the building for his music project?" she asks. I say I'm going to find out more that afternoon. She laughs: "Oh, you must e-mail me and tell me what you think!"

I find Paul Allen's headquarters in the suburb of Bellevue (Microsoft's grassy "campus" in Redmond is nearby). The building is discreet, square and boring. The carpet is beige. Would I like a drink? I ask for water. "Normal or with bubbles?" I say bubbles. "And what flavour?" It is such details that set the seriously rich apart. As I sip a bubbly raspberryish something, I learn that Paul Allen originally thought about displaying his Hendrix collection in a gallery. The size mentioned was about 10,000 square feet and his sister and executive director Jody Patton was duly sent out to investigate. She reported back that such a gallery of artefacts would be boring. Hendrix would have hated it! The project grew. Why not do rock 'n' roll in general? Why not interactive? The idea was deemed to be "cool" - a ubiquitous Seattle word - and some serious rock 'n' roll shopping began. What started as a gallery ended up as a 130,000 sq ft museum called the Experience Music Project.

"It's a gift to the city. Paul is putting in $60 million to get it started. This is his thing. There is now a staff of 30 and by the time we open it will be 75," says project spokesman Jason Hunke. "There was a very aggressive international search for an architect. Paul and Jody wanted world-class. They wanted something different from anything that had ever been done." They chose Frank Gehry - who has just completed the titanium- clad Guggenheim in Spain - and, true to his brief and his reputation, he has designed a building that will be the wildest thing on the West Coast, never mind Seattle. Inspired by electric guitars, the model swoops and soars in a smashed-up kind of way. If anything can be said to personify the "Purple Haze" chord, this is it.

Some love it, others call it an abomination. No one denies it will put Seattle on the international map, though, and the staff in the beige building in Bellevue are thrilled. The museum's web site is already off and humming, and the bulldozers have started to dig up the site at a parking lot next to the Space Needle. The groundbreaking took place on a Friday the 13th to the sounds of the Kingsmen, Mud Honey, and the Presidents of the United States of America. At some point, Paul Allen threw off his coat, picked up his Fender Stratocaster and started jamming with the guys on stage. "It turned out to be awesome," says Hunke and I wonder, not for the first time, if the city is ready for such largesse as this.

Seattle got lucky in the 1990s. A rough-and-ready port underpinned by the huge aircraft manufacturer, Boeing, it has now re-invented itself as the city of high caffeine, high energy and hi tech. One magazine summed up the new Seattle as, "smug, but with some justification", and in parts of downtown you can feel the money. There is an entire store dedicated to Barbie and a car repair shop called Fat City.

Trish Millines's office is a few miles and a world away from downtown. In Columbia City, the stores have names like Hong Vu's groceries or Poodle Palace ("We specialise in large and matted dogs") and advertise fabulous nail jobs and Nubian hairstyles. Millines's Technology Access Foundation is across the street from an Ethiopian restaurant and she welcomes me wearing shorts and a sweatshirt. We talk in a room that contains $25,000 worth of computers and $300,000 worth of software.

In a matter of weeks, this equipment will be distributed to community centres in the city's poorer areas to be used by "children of colour" - in Seattle terms that is blacks, Hispanics, Native Americans and Asians - in a bid for them to join the technological revolution. The foundation supplies computers, programmes, software, teachers and support. It has an ambitious internship programme in which hi-tech companies can "adopt" 14-year-olds and shepherd them all the way through college.

Millines is the daughter of a single mother who scrubbed floors and cleaned houses for a living and is the exception that proves the rule. "There was no question that I was going to college. That was what my mother worked for," she says. Millines went on a basketball scholarship and emerged as a computer programmer. She joined Microsoft in 1990 and left as a millionaire six years later. "I never thought I'd have this much money," she says. "But one of the things I can say is that I gave away as much as I kept. This is something that I was born into. My mother always gave through the church. I can remember selling toothbrushes door-to-door in a rich, white neighbourhood to raise money for her church. It was entirely too funny."

Microsoft fully matches staff contributions to non-profits up to $12,000 a year each and many employees "max out" on their contribution. "Sure I gave money," says Millines. "That's the easy thing to do. You write a cheque and then you're done. I taught programming classes and sat on boards for non-profits. But I knew I wouldn't be at Microsoft forever. I'm not a corporate person. I knew I was going to go and do some sort of philanthropy. I didn't call it that. To me it is just giving back." Millines personally funded the foundation for its first year and is now busy raising money for the second year. "We will run this like a business and we got those skills from Microsoft. Our outcome, our product, are these kids. If they aren't succeeding, then we are not succeeding."

Scott Oki also succeeded against the odds. He began life in a three-room tenement in central Seattle, where he lived with his parents, his grandmother and his brother and sister. "We did not even have a private bathroom. We were not well off but we were always connected to the Japanese community there," he says.

He went to university, got into the hi-tech business, wrote Bill Gates a letter and was hired in 1982. Ten years later, he was a senior vice- president of sales, marketing and services and, thanks to the stock options, wealthy beyond his wildest dreams. "But when you are with Microsoft that is the last thing you think about. There are worlds to conquer and no time to dwell on the trivial stuff like what your net worth is that day. When you do start talking about numbers, it is amazing. Ultimately, you just pinch yourself and say: OK, so what do I do with this?"

What he did was to retire at 42. The idea was to play some golf. Scott Oki is a serious golfer. He develops golf courses, he owns them, he is passionate about the game. But it wasn't enough. When Microsoft went public in 1986, he and his wife had thrown a few thousand shares into a foundation and now he turned his attention to it. "It all started out as a tax thing, really," he admits. "But by the time I retired, because of the splits, there was a lot of money there." He wrote cheques but also got personally involved, bringing the incredibly focused world of Microsoft into the non-profit realm.

We are talking in the foundation's offices in a converted Catholic church in Bellevue. Sofas dot the huge room. There are antiques and Japanese pots with palms. An Arnold Palmer golf book graces an expensive coffee table. He says he now is as busy as he used to be at Microsoft and that burn-out approaches. I don't believe him because he seems so excited about everything. "I believe that philanthropy is very similar to other things: in order to get good, you have to practise it. I can remember when we were asked for our first million-dollar gift. My wife and I were dumbfounded. A million dollars? You have got to be joking! We thought long and hard about it and, at the time, believe me that was a sacrificial gift. In the end, though, that grant led to $11.3 million in new funds raised for a children's hospital. It is exciting." He smiles. "And once you write your first million-dollar cheque, then when you do a half-million-dollar thing, it's like nothing!"

His interests range from the mammoth University of Washington to founding the Japanese American Chamber of Commerce. The latter may be the closest to his heart: his parents were interned during the war and one of the chamber's projects is to document this forgotten chapter in American history and to digitally record the life histories of the 116,000 internees. "This project could have huge scope and scale. Would it be timeless? Absolutely. And it would be accessible by billions around the world because of the Internet." It's the kind of thing that makes history.

What would you do if you had a million dollars? This is the question that keeps sneaking up on you in Seattle. Would you be like Ida Cole? She retired from Microsoft at 43. A year later, friends pointed out to her that the city's historic Beaux Arts theatre, the Paramount, needed to be saved. At this point, she lapses into Softie-speak: "I did diligence on that project for an entire six months." That means that she researched it ruthlessly. In the end, she bought the building, set up a non-profit company to run it and volunteers her time as its executive director. "Whenever I get frustrated, I sit down in that theatre and those walls just talk to me. Every major act in the world has played there."

People like Ida Cole and Scott Oki are pioneers but the world of hi-tech moves too fast for them to be that for long. Former Aldus Corporation president Paul Brainerd is another new philanthropist and is determined to help others along the path. This year, he founded a "giving circle" called Social Venture Partners. So far, 130 people have committed to give $10,000 each and at least that much of their time over the coming two years. The idea is to pool resources and use the venture capital model to take risks and give money and brainpower to the non-profit world. "This is a learning environment. It is a safe place for this new generation of people who have made this kind of money. They don't come from rich families. They don't know what to do with their money," says Brainerd, whose own parents owned a shop in a small town. "This is a great way to make a difference. What's really exciting is the feedback. You know, people come up and hug you! That just doesn't happen in business."

Of course, there is feedback and feedback and the kind that Jimi Hendrix generated was hardly cuddly. But councilwoman Tina Podlodowski believes Seattle is on the brink of an artistic revolution. "We have not broken into the big time in terms of the arts, but I think we are poised to do that. The original group of Microsoft people were all computer geeks. This next wave are all content people: artists, writers. I see Seattle going through a real renaissance. I think this city is trying to figure out what it wants to be when it grows up."

One thing is certain: it will not be boring. Podlodowski, for instance, is applying much of her Microsoft smarts to raising money for gay and lesbian families. "I am the out lesbian on the council," she announces. She and her partner have a 22-month-old-daughter and a baby boy named Jackson. "My partner is the biological mom and the donor is a friend of ours. It's legal for me to adopt them here. It's not a big deal in Seattle," she says breezily. "In fact, there is a big gay/lesbian baby boom happening here."

Hendrix. Lesbian parenting. Venture capital philanthropy. What would the Medicis say? If they lived in Seattle, it would have to be "cool ".