I've been on an Orson Scott Card kick lately. A couple of recent ones (besides the obvious Ender's Quartet):

Treasure Box
Enchantment
Songmaster

I would recommend either of the latter two first, although the first one won't disappoint.

...and I also recently finished reading Quicksilver by Neal Stephenson. I would recommend anything by this guy, but I wouldn't start with this one, as it is a "difficult" read (plus, it's part of "the Baroque Cycle", and he's already written the next two! Can you believe it!?!).