The Extended Phenotype: Richard Dawkins. Applied Cryptography: Bruce Schiener. Linear Algebra: Friedberg, Insel and Spence. Steven Pinker: The Blank Slate

I've recently finished Dan Gilbert's: Stumbling on Happiness and I highly recommend it. It's witty and gives you a very different way of looking at what you think makes you happy.

I know these aren't start-up books, but unfortunately I haven't read any to recommend.