I thought this could be handy:

http://www.fotosizer.com/

With this small free software, you can, among other things, batch resize pictures, so that they will be the perfect size for your e-reader. :)

http://www.fotosizer.com/images/fotosizer_screenshot1_big.gif

This looks like a good little application. I personally use Irfanview's batch-resize, but it's a general graphic-related application that I also use for other things, whereas I'm rather fond of little job-specific applications like this. Thanks.

Cheers,
Marc