Bookletters, perhaps the least recognized feature on our website. I've subscribed to the Audio and Lifestyle newsletters in both email and RSS formats forever. Added Book Sizzle because everyone else seemed so enamored of the concept.
NoveList, the capitalization of which I need to correct on our Research Tools page. I went with Science Fiction>Alternate Histories. This is a tool that really speaks for itself, but would be pretty handy for putting together book displays too.
My reading selection tools are a mix of buzz from my social networks, references from my RSS feeds and the random stuff sitting on the shelves of my house that I've never read. But I'm not nearly the voracious book reader that I once was, so I hardly need more books to never get around to reading. Sad.