Amazon's Ebook The Future of Reading?
http://www.baen.com/ sell reasonably priced ebooks and have some free (as in beer) ones. Good start for an SF library, we just need a few more publishers* to follow that example.
... and, of course, for this new device to be able to accept them.
* a good start would be one that does detective stories - that itself might be sufficient to bootstrap ebooks to a larger audience.