RPG wise: Going through SR4 books by topic (I.E.: Magic, Hacking, Augmentations...)
Otherwise:
Documents of the Christian Church, Edited by Henry Bettenson & Chris Maunder, New Edition.
A Short World History of Christianity, by Robert Bruce Mullin.
Multivariable Calculus, by Jon Rogawski.
Been a while since I read for fun, recently (SR and random bits of 3.5D&D aside). Off the top of my head, Wraeththu by Storm Constantine and Chronicles of the Black Company by Glen Cook. Oh, and Heaven's Net is Wide by Lian Hearn.