I mostly read ebooks, but mostly buy pbooks.

I never really read the classics while growing up, so sites like Project Gutenberg will provide me with reading material for a very long time. I suppose that I could grab print copies, but ereaders are simply cheaper and more convenient in the long run.

In terms of modern books, I buy used or grab freebies. Since there isn't a market for used ebooks, print it is. (My apologies to the authors of the world, but I have a hard time justifying $10+ for a few hours of entertainment.)