I love Call of Cthulhu and Vampire: The Mascarade. I play D&D once in awhile, but if I'm GM, my stories are very similiar to the Call and Mascarade. Even my friends get the games very closly related. On one of them that is a Mascarade game, my Brujah character, who is taking over the world, and has conqured South America and Africa, found the real Necronomicon. He tried to take over Europe by summoning Cthulhu to destroy it, but it turned out that Cthulhu destroyed all of Europe and Asia, and set up a kingdom thier. Haven't got to play it in awhile, but I'm sure I'll lose Africa, and the rest of the world.
Guild Wars. I bought it over the summer and I can't stop playing it. Except for times like this when my computer is in the shop.
You should try World of Warcraft. What is irratating about Guild Wars is you get a private world map, and only those in you party when you leave town are in this world. Warcraft does cost 15 a month, but it's almost like living an entirely different life. The servers are the only things seperating players, which means you can leave town not in a party, get to the quest destination, and complete it yourself, or join a party if there are other players thier. I highly recomend joining a party though, since you'll level up faster.