K, I'll play...
Just finishing A Dance With Dragons by George R. R. Martin. It's the fifth book the Song of Ice and Fire series, better known as The Game Of Thrones. I have enjoyed the four previous books and I am enjoying this one just as well. It's like reading a good history book, only with more sex and violence, plus dragons and all kinds of other sorcery.
Before that I read The Sleepwalkers: How Europe Went to War in 1914 by Christopher Clark. It's a very long book about the people and politics involved in the lead-up to WWI. It's well written and it kept my interest through all 1200-plus pages.
Before that it was Cadillac: Standard Of The World (An Automobile quarterly library series book) by Maurice D. Hendry. Actually I haven't finished this one - I plan to go back and finish it. This is a very well researched and dense tome about the history of Cadillac up until the early-1980's. There is a TON of info and great pictures. This book was originally written in the 1970's and has been updated and revised a few times. My copy is the 1984 edition.