Probably not a classic for the ages, but I enjoyed the new Max Brooks novel, Devolution. It does for Bigfoot what World War Z (the book, not the film) did for zombies by injecting a bit of versimilitude and detail stolen from reality.

Freeze Frame Revolution by Peter Watts combines epic mind bending ideas with some hard sci-fi details.

Piranesi by Susanna Clark was very Iain (M) Banks style epic fantasy.