Realm of the Mad God is even better on that front: it auto-generate a name for you, you just hit "Play" and you're in the game ready to rock (you can edit the game once you're hooked of course, and create a formal account, and start paying your dealer, but the initial experience is "hit play and you're playing")
I thought the most clever part was how it throws you (pretty much) directly into killing your first boss monster. You feel awesome within a few minutes of starting, immediately before getting told to go kill more boss monsters.
