City of Heroes is a horribly addictive game.
How do you ask? Here's a case in point: a friend of mine set up a loaner computer for me to take home and play, after dealing with network issues (I discovered that the loaner box didn't like my DSL modem, and I had to get some additional parts—keyboard, cables for an old 14" monitor I had lying in the closet, that sort of thing—to build a makeshift network) I sat down and started to play yesterday.
Fourteen hours later, my body told me to shut down.
I swear, I need an alarm clock or something...