See medieval cities, meet elves, marry: anything can happen in the dungeon
"Benjy has a lean-looking tiger body, and wears a beautiful black and purple coat, decorated with a white mane under his neck. In the sunlight his normally green-brown eyes flare a curious emerald green."

What Benjy looks like in real life is anyone's guess, but for up to 14 hours a day the only way you will see him is as described above. He lives half of his life in a game called Nanvaent, a Multi User Dungeon, or MUD, where he shares a fantasy world with the 30 or so people who are linked via the Internet to the same game. It is the cyberversion of Dungeons and Dragons, but because you can play it alone, it can cut you off even more competely from the real world. In this virtual dungeon you can live a lifetime - travel through medieval cities, cast spells, drink beer, deposit money, talk to your fellow human beings, dwarves and elves, get married and divorced, kill monsters, die and be resurrected. All this without a single graphic - MUD relies on text and imagination.

If you play long enough, you can advance your character and rise up the career ladder from mere player through creator to a god, building your own dungeon. A study in 1992 suggested there were around 170 MUDs: there are now about 600 with 60,000 regular players.

Most "Mudders" are students taking advantage of their ability to use the Internet for free to spend as long as 10 hours a day playing. Many say this alternative existence has wrecked their academic or working life. Most say they are addicted.

Cary Cooper, Professor of Psychology at the University of Manchester Instititute of Science and Technology, has studied the addictive nature of basic computer games. This, he says, is more addictive. A MUD is all- encompassing. Not only do you have scenery that changes - divorce courts following on from wedding chapels - but the infinite complexity of dealing with other human beings. The game has everything that real life has or should have, except pollution, traffic and reality.

For many young people the social and promotion prospects in the alternative world are far better than in this one. Sparrowhawk started playing Nanvaent almost two years ago and has spent 133 days of that on the MUD, about a third of his waking life. In this world he is a third-year university student. In that world he is a Lord.

"I met all the people I would consider my friends through Nanvaent ... The computer takes away any prejudices people have ... There is no age, sex, weight, height, looks ... no limits. There are a lot of things that I feel are wrong about me - the fact that I don't have any dreams. I'm not particularly well-off. I don't have a girlfriend. Perhaps that is what I come here for, to help find my dreams and make them. Mudding affects my outside life. I have slept through lectures because of it. I only logged off a week before my exams."

The MUD has also begun to seep into other areas of life. The Internet's potential for drawing together people from the far corners of the earth has been known for some time. On Nanvaent the courtship and honeymoon might be an adventure in the dangerous dark elf tunnels with the lovers defending each other with spells and prayers. There is also the opportunity to try out marriage in Nanvaent's wedding chapel with a virtual priest and audience.

Jackal met his most recent girlfriend Dragonfly on the MUD. He is a student in New York and she lives 2,300 miles away in Canada. They are married on Nanvaent and are discussing marrying in real life, even though they have never met. "I've known friends here get engaged and married. It's easier in that you can be more comfortable if you're the shy type ... without ditching your real-life personality. The only reason I don't ask Dragonfly for real now is that I want to propose properly.

"Most non-Netters don't understand Net relationships or those springing from the Internet. It is true that some people use it for an escape. Too many people allow themselves to get lost here. They forget real life. There are a few players who fall in love after a short conversation, for instance. They cling to player after player, looking for real-life relationships. There are definitely those who play because they don't have to be themselves. Some dislike their lives, and take in the fantasy the MUD has to offer. One can do or be anything here."