For Book Fiends - The Complete Review.
For Game Fiends - Orisinal. (Definitely not your typical web games. Worth a look just for the delicate artwork used in the games.)
For Food Fiends - Food 411.
For News Fiends - OhMyNews International.
For Kitsch Fiends - Archie McPhee - Outfitters of Popular Culture. (Immediately amused by the Librarian Action Figure.)
For Search Fiends - Clusty.
Faves PostSecret and McSweeney's also made the list.
**edit** Just-Found New Fave: Go Fug Yourself. Celebrity fashion crimes exposed. Check out the Bai Ling and Chloe Sevigny sections for a taste of the fun.