I roleplay for the obvious escapism.  Sometimes I just want to be someone who isn't me, but I also just plain enjoy writing and roleplaying is a good creative outlet when I don't feel like building a world from scratch.

There was somewhere on here...I can't remember the name of the thread or who posted but they compared roleplaying to an MMO.  "Writing a story is like playing a game in singleplayer mode," they said, "And roleplaying is like turning on the multiplayer."  or something to that effect.  This is exactly how I feel.  I'm pretty shy in real life, almost to the point of being antisocial.  I don't watch the same TV shows that a lot of other people do, I don't read the same books, or listen to the same music...I have very little in common with the people around me.

But when I'm roleplaying, I don't have to be anything like the people that I'm roleplaying with; the thing we have in common is the world in which we "live", and that's enough.  Some of the coolest experiences I've had online were when I was roleplaying.