Here are some that didn't:
Here are some that did:
Now this is interesting, a list of good books that should make good movies:
Especially interesting because the list is from 2007 and several of them have since been made -- and mostly they didn't work out.
And this is just a long list, a slushpile if you will:
Finally, this post would not be complete without a dishonorable mention of the worst rip-off of all: notStarship notTroopers. Hm, wish somebody'd actually make a movie of the book Starship Troopers someday.