Let's see, last real book I read (and I actually cheated and listened to it), was actually the Ringworld books or maybe Protector? Larry Niven has this entire series called Known Space. I'm sort of into it though the second and third Ringworld books got really fucking weird.
Main idea around the Ringworld is that an alien race built this fucking massive Ringworld and this guy crash lands on it and is trying to get off of it. There are all kinds of weird "indigenous" people there (as much as you could call it that on an artificial world) and the thing that was particularly interesting was just how much attention this guy pays to explaining all the crazy science behind everything. It was a cool book just for the massive scale of everything and all the interesting aliens and stuff.