There's a tonne of free reading material out there these days. A lot of it is pretty decent... some of it not so much. But I'm looking for the REAL good stuff. Quality stuff that you would have been happy to pay money for.
So what are some of the free ebooks you've found that you really enjoyed? When I mean free... I mean permanently free (within reason... no one can predict when things may suddenly change). I guess the best criteria would be
(1) free at this very moment and
(2) probably will be free this time next year.
Just going off the top of my head, I think "Blindsight" by Peter Watts is right up there in terms of quality and engagement.
http://www.feedbooks.com/book/976