1) Everything currently available in full from Baen (400++ books) that isn't an eARC. I'd list books from PG, but they aren't 'purchased.'
2) The ones I got with the $50 early-purchase deal-sweetener (and no more!)
3) Whatever Baen publishes, or makes available for purchase through WebScriptions. That means mostly SF, Fantasy, and a wee bit of non-fiction. I'll start patronizing other publishers when they start offering DRM-free books in formats I can use. Unlike many, I keep books and re-read them, so having DRM turn what should be a purchase into a "temporary purchase" is not acceptable to me.
4) It goes the other way. I buy the bits. Then, if I really like the book I buy the paperback when it comes out. If I think the author walks on water, I buy the hardcover too. But the list of authors I buy in HC is really really short.
5) I picked up the various Flinx books by Alan Dean Foster, and 'The Tales of the Otori' by ??? with my initial $50 credit from Sony. I'll be back for more when they start offering DRM-free books at reasonable prices. Reasonable prices in this context means "below paperback." There's no reason they can't sell at that price and STILL provide a higher royalty to the authors than paper sale does. We have an existance proof, after all -- Baen does this already.