DCH House Rules - New rules for Third Edition campaigns.
More Action Fun - Golden Age campaign set in 1932. Includes background, characters, and conversion notes for Champions and GURPS.
The Unofficial DC Heroes JLA Source Page - Features character descriptions from the Grant Morrison/Howard Porter era of the Justice League. Also includes a gallery and a map of the Watchtower.
Writeups.org - Searchable detailed writeups of characters from all media--comics, movies, tv shows, and other games.