Kindle DX

I have exciting news! I just ordered a Kindle DX from Amazon. It should arrive in the next couple weeks. I was torn on whether to buy one, but was finally won over for three reasons (in order of importance). (1) You can view PDF document with the Kindle DX, unlike with the previous instantiations of the Kindle; most academic papers are distributed in PDF format. (2) You can access Wikipedia wirelessly using the Kindle DX. (3) Textbook publishers are partnering with Amazon to provide cheap, eTextbooks; reading material online rarely bothers me, but keeping old, clunky textbooks around on the premise I may one day use them does.

All that being said, there is one service I wish existed. I would like to trade in my hard copy books for soft copy versions. After all, I already own a copyright on the material. I don't like lugging books around from place to place on the premise (again) that I will one day re-read them. Nevertheless, I frequently do re-read books, so my collection follows me. One additional advantage of ebooks (beyond portability) is searchability. A couple weeks ago I spent a full half hour searching my hard copy of The Last Days of Socrates for a passage I could have easily found electronically in mere seconds.

Is anyone aware of such a service, whereby I can exchange hard copies for soft copies? I would even pay money for the service (perhaps $1 per book). On this note, I am curious what the price difference is between used hard copy books and new soft copy books... perhaps I shall look into this. Hmm, maybe there's even a business idea here. If you steal the idea, just tell me about your service so I can use it :).