Haven't used it in months
I used my prs500 a lot when I first got it, until I read all there was that interested me in the public domain. Now all I'm interested in is copyrighted material, so I would have to buy the books if I wanted to read them on the Sony Reader. I have a great public library at my disposal that can get any book I'm interested in, on PAPER, and for FREE. So why would I buy an electronic book when I can read it for free, with unbeatable contrast, eternal battery life, and a robust construction?
I have come to the conclusion that ebooks are good, but libraries are way better.