Non D&D - Changeling. That's pretty much it. I bought and played GURPS and DC Heroes, and otherwise stuck with D&D in my decade or so of gaming. Then again, I got all my books from Waldenbooks for years (employee discount) so my options were a bit limited.
D&D - Various 2nd edition modules that looked cool (Tale of the Comet, Rod of Seven Parts, Firestorm Peak)
Enemies and Allies: I should make an NPC with the one or two new feats in there...and eventually, someone will need a quick new character, and they can use an iconic....I can hope, anyway
Otherwise, other than the Hero Builder's Guide and most of the modules, I have bought most every WotC 3E product and the hardcover Scarred Lands books, and gotten at least a little use out of all of them.
