Marc Horowitz's website is well named: ineedtostopsoon.com. You probably haven't heard of Horowitz, but if you're curious about art, comedy and the ways the internet is blurring the distinctions between them, you might log on to his site intending to glance at it for a moment, only to find the minutes slipping into hours. Even while the words "I need to stop soon" are echoing round your head, there's always the temptation to click on one more link.
The biggest time-swallowers are the amiably rough-around-the-edges YouTube videos of Horowitz's Pythonesque sketches, from the Underwear Trying-on Contest to the operetta about how he invented the internet. Get past them and you come to the video tours of Horowitz's gallery shows in Paris, Geneva and Como. Each exhibition is titled The Centre for Improved Living and is stocked with sculptures, sketches and posters that could, in a semi-ironic way, make life easier. Among the exhibits are a rug for sweeping things under, a kit that enables you to take revenge on noisy neighbours, and a card which reads "I'm sorry for breaking into your bank". ("Just in case you break into a bank, you have an apology letter already written," explains Horowitz.)
Also on the website are videos of Horowitz's performance art, including his Errand Feasibility Study, for which he rode around San Francisco on a pack mule. And once you move on from the videos, there are suggested daily activities and photos which reveal that Horowitz, aged 30, has a certain kind of nerdy chic. There are even doodles and hand-drawn T-shirts available for a few dollars apiece.
It's an inspiring, life-affirming scrapbook, but after a couple of hours or more you still might not be sure whether Horowitz is an artist, comedian, cartoonist, designer, film-maker or just a student with too much time on his hands. A mere 10 years ago, he would have had to prioritise one career over another, but thanks to the internet (which he didn't invent), every idea in his head can be funnelled in a website which, he says, gets 25,000 hits a day.
Perhaps his forthcoming show at London's Hayward Gallery might help to settle matters – but probably not. As part of the Hayward's Laughing in a Foreign Language season, Horowitz is bringing his Centre for Improved Living to London. This time, it's going to feature workshops ranging from "How to Make a Killer Sandwich" to "Ways to Get in a Better Mood (Without Being Incredibly Destructive)", as well as a talk show which will be webcast from the gallery three times a week. With a matter of days to go before the first episode, Horowitz still doesn't know who his guests are going to be.
Watch Horowitz's gallery tour in Paris
"I'd like to get some Japanese people with British accents," he says on the phone from his home in Los Angeles. "I don't mean that in a racist way at all, there's just something amazing about people who look Japanese and sound British." So is it comedy or is it art? "I asked myself that question while making pancakes today," he says. "Donald Judd's single requirement of a work of art is that it be interesting, and I agree. If you're making engaging work from your soul, what does it matter if it's art, comedy, or both?"
As a student, Horowitz wasn't set on either discipline. "I grew up really poor, and I didn't want that for myself," he says, so he studied marketing at Indiana University. But in an effort to keep up his painting hobby, he talked his way into the university's art department and immediately realised that this was where he belonged. Despite the discouraging advice of a military uncle, whose refrain on the subject of an art career prompted his nephew to buy the "ineedtostopsoon" domain name, Horowitz proceeded to the San Francisco Art Institute, where he concentrated on painting until his two "new genres" tutors forced him to try something more conceptual.
For want of a better idea, he stood at a busy trolley-car stop and handed out blank pieces of paper to passers-by. "Japanese tourists wanted to take photos of me. Old men would shake my hand and thank me for doing the Lord's work. Homeless people wanted me to write letters for them to their families, but they didn't have an address to give me. I didn't document it or anything, but I thought it was interesting to get so many different reactions to a piece of blank paper."
This experience led to his specialising in "social research". Reacting against his business background, his first stunts tended to have an anti-corporate undercurrent. A favourite prank was to leave a mobile phone in a Starbucks pastry and then ring it. "The Starbucks guy was so angry you'd think I'd put anthrax in there." He also staged major, month-long interactive performance art sessions, such as remodelling a gallery as an office staffed by fellow artists and branding themselves Sliv & Dulet – "just the worst names possible" – a firm dedicated to "finding problems to your solutions".
His most high-profile project has been his National Dinner Tour. While working as a photo assistant on a catalogue for the furniture chain Crate & Barrel, he slipped the message "Dinner w/Marc" followed by his mobile phone number into one of the pictures. When the catalogue was published, he received phone calls from all over America, and beyond. He packed himself into a campervan and toured the country, breaking bread with as many of the people who'd called as he could. He was soon appearing as a talk-show guest and he went on to be listed as one of People magazine's "50 Most Eligible Bachelors".
Watch 'The National Dinner Tour'
His planned follow-up is to blow up his signature, superimpose it on a map of the US and then drive around the signature. It's the kind of sublimely pointless odyssey that's done in Britain by Dave Gorman and Danny Wallace, but rather than being a comedian moving towards art, Horowitz is heading in the opposite direction: he's doing more and more stand-up and now has a Hollywood agent.
Maybe the artist/comedian/prankster categorisation is precisely what he's poking fun at. "In the UK and US you have to say what you want to do at 15. I'd just like people to get the idea that you don't have to pigeonhole yourself. You can hand out free advice in the street or do all your errands on a pack mule. These things don't cost a lot of money."
Marc Horowitz: The Centre for Improved Living is at Hayward Project Space, London SE1 (0871 663 2501) from 18 March to 13 April
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