Gonzo - Stephen King's Insomniac and his Gunslinger series are very firm favorites of mine. I've anyone hasn't read Great Apes by Will Self I highly recommend it, I bet you can't get halfway through it and start looking at your fellow human beings in a different light.
The Dark Tower series is still my favourite thing I've ever read. Also, if some have never read Stephen King then I'd recommend the Stand, so so good.