Second Life is an interesting place to visit. It's a virtual world where you exist as an avatar, and you can interact with other human-controlled avatars. It's only been in existence for three years, and it recently signed up its six-millionth inhabitant.
It's still a work in progress. It has teething troubles. But it has potential. And it is science fiction become fact.
Remember Tron? Disney's venture into computer animation? A world existing inside a computer system? It's here.
But a better description of what Second Life is like from an SF perspective is Michael Moorcock's Dancers at the End of Time trilogy. In it, the world is a playground for its population of aesthetes, who throw parties and create marvels out of the world's energy field. The most eminent citizens if that world are the ones who produce the most fantastic creations, just as they are in Second Life.