I have bought very few hardcover books in my life, not just because paperpacks are cheaper,but because I like paperpack format so much more. I often carry books with me for reading and hardcovers don't work for that. Carrying just an ebook reader (in my case a mobile phone) is very nice indeed. I don't even seem to have problem reading backlit screen.

Lately I've been buying almost exclusively ebooks. Fortunately some places sell interesting DRM free content:

The only books I have bought on paper are comic books. That form can't be shown very well in a reader that still fits to my pocket. But most of what i have bought are based on webcomics and I can still really recommend buying them:

If they would just now sell these as ebooks. It's funny old world. :-)