But the story is a piece of Silicon Valley lore because of the reason Steve Ballmer allegedly threw the infamous chair. He wasn't aiming at a person. He didn't hate his table. He was fired up, because one of his engineers was leaving to take a job at Google. Google! And Google IS in Silicon Valley.

The guy is passionate.

One project he's spending time on in retirement: USAFacts. It's a trove of information about where our federal tax dollars really go – you can find it at USAFacts.org, and play with the numbers yourself. Ballmer started digging after his wife asked him to get more involved in the family foundation's charitable work. Ballmer is passionate about making sure kids have the opportunity to do better than their parents did financially. I asked him if that passion is what motivated him to do a massive data project.