The Tortilla Curtain is a very good book. It was one of my book club's selections last fall and there was a lively discussion....lots to think about there!
I hate to admit that I haven't managed to tackle The Elegant Universe. Its on my shelf and I have watched the NOVA version, but I can't get quite motivated enough to read it on my own. Hubby did though. I also gave Brian Greene's other book, The Fabric of the Cosmos: Space, Time, and the Texture of Reality a whirl because it is supposed to be a little more accessible, but alas, I think I only managed about 50 pages there before I got distracted by a more shiny book.
Just finished Beasts of No Nation by Uzodinma Iweala which is another excellently written novel. It is a first person narrative by a young boy in a war torn African nation who is pressed into being a child soldier.
Currently working on Secret of Scent by Luca Turin which is also very interesting. He is explaining the organic chemistry behind the various components of perfumes (both industrial and fashion scents) and I am just not getting to the part where he is talking about how the currently accepted theory of how we identify scents (receptors for certain shapes) does not work well. Later he will show how another theory, that we read molecular vibration, fits the evidence much better. (I know where this is going because I read a book about the author and his research called The Emperor of Scent previously)