Ereaders and Ebooks

I went and got myself an ereader today, and I was wondering what you guys think are essential things to keep on it.

Also I was wondering if there were any good domains of free books.

Project Gutenberg should be your main source of ebooks. Without it we would not have ebooks! This is the organisation that created ebooks in 1971--your looking at thirty nine years worth of digital books...

http://www.gutenberg.org/wiki/Main_Page