KoL
So thanks to Jaap, I've now been initiated into The Kingdom of Loathing. It's the creation of Asymmetric Publications, and it's described as "a comical RPG" that's currently in open beta.
It's brilliant, in that it's a Web browser-driven adventure game comprising nothing but simple, hand-drawn black and white graphics. The six different character classes you can play include "Accordian Thief," "Seal Clubber" and more, and you go up against dread monsters like the "Sabre-toothed Lime" and ninja snowmen. It's a hoot. I strongly recommend it.