I think the thing I love the most about the book The Professor and the Madman is that its Wikipedia article's "see also" section cites crowdsourcing.
Simon Winchester is arguably (ok, not arguably) one of my favourite authors. The first thing I read from him was Hong Kong: Here be Dragons and I quickly followed that with The River at the Center of the World: A Journey Up the Yangtze, and Back in Chinese Time (I'm not going to lie, reading these two books played no small part in my decision to go to China between my third and fourth years at university). At 17 I was bored with geography class, and being the slightest bit sarcastic, I wanted to cite something ridiculous for my final big project. The titles drew me into Winchester as an author, but what kept me going back to him is I loved how he wrote. He made these huge subject matters accessible, something I could understand. I was thrilled when he wrote The Map That Changed the World: William Smith and the Birth of Modern Geology in 2001 (look, it's not a secret I'm a geek).
Either way, the Professor and the Madman is one of my favourite books of Winchesters - how could it not be? It's about the writing of the OED (amazing) and I found out it was basically written by an American living in a British asylum, who wrote it because he was well off enough to collect books, quite rare books and while he was deemed criminally insane because he murdered some guy in a fit of paranoia he was given enough freedom to write one of the greatest dictionaries of all time (10,000+ entries of it, at any rate), all the while having some of his rare book collection coming from the widow of the man her murdered, and thought there were small people in the floor and ceiling who came out at night to torture him. It's also important to realize that Minor and Murray had a close friendship for over two decades - but only through correspondence. After Minor (who also, by the way was an American Doctor) sent ten thousand definitions to the dictionary, a puzzled Murray set out to visit him, and only then found out Minor was a murderer, clinically insane and locked up in Broadmoor (England's harshest asylum for criminal lunatics).
The book is brilliantly written, and the subject matter is completely fascinating. Go read it.