PotterSues --Someone's livejournal, on which they review Harry Potter Mary Sues in the most humorous way.

FictionAlley --A good place to post your fanfiction, where you will get a lot of exposure and good, constructive comments.

Star Wars Databank --Where you can find out all you need to know about Star Wars Canon and EU characters, events, and technology.

Harry Potter Lexicon --The "Databank" (see above) for Harry Potter. Has some truly dizzying intellect behind it.

LyricsDot --An easy way to find the lyrics for your songfic even if you don't know the title.

Hp and LOTR-the Similarities --Goes through all sorts of similarities between Harry Potter and Lord of the Rings.