Netflix has a fascinating look at the Microsoft co-founder with a new three-part documentary, Inside Bill's Brain: Decoding Bill Gates directed by Davis Guggenheim. Guggenheim is probably best known for directing the Academy Award-winning Al Gore documentary An Inconvenient Truth. With that in mind, it's no surprise that the bulk of Inside Bill's Brain focuses on telling the story of Gates's active pursuit of global health and other social causes.

There's also a healthy amount of Silicon Valley lore about the beginning of Microsoft, and a look at Gates's childhood. But even if you're an Apple die-hard like me, you have to give the guy credit for creating two of the most important enterprises of this or any generation. One is the most valuable corporation on earth and the other is a massive charitable foundation.  

Still, even if you are well-versed in the history of Microsoft, or Gates in particular, there are probably a few things you haven't heard. Here, in no particular order, are five fascinating things you probably did not already know about Bill Gates. 

When he was a student, he tried to intentionally fail a test. 

There's a story about a test that Gates had to take in order to enroll in private school, which he really didn't want to attend. So, he decided he'd just tank the test to disqualify himself. Except, being Bill Gates, he couldn't bring himself to fail. He, of course, passed and got accepted.

He travels everywhere with 10-15 books.

One of his staff members keeps a bag full of books and refreshes it every few weeks to make sure Gates has a constant supply of reading material. These aren't light reads, either. Gates reads things like Fundamentals of Deep Learning and Quantum Mechanics and Algorithms. You know, the stuff you pull out when you have a few minutes between meetings.

He takes a week every year just to think.

Years ago, Gates started an annual ritual of getting away for a week to be by himself to just think. Picture it: Gates, a small cabin, a stack of reading material, a pen and notepad. When your brain is working on solving some of the world's biggest problems, I suppose it makes sense to slow down and give it some time to work.

He once wrote a letter to major research universities about a project...and they didn't even bother to respond.

You'd imagine that if Bill Gates writes a letter to anyone, he's likely to get a response. But when he sent a request for a partner on a project to bring better sanitation to the poorest areas of developing countries, most of the most prestigious universities in the world didn't even bother to acknowledge his letter.

Researchers told him it would cost $200 million to eradicate polio, so he gave them twice that much.

One of the problems Gates says comes with running a foundation is that people will often tell you they need whatever amount of money they think you'll say yes to. That's a problem...because it's not always the same as the actual number needed to tackle the issue.

Once, when the Gates Foundation decided to get involved with the effort to make polio the second disease erased from the face of the earth (smallpox was the first), he felt like the scientists were low-balling the amount they needed to make a real difference. So, he doubled the amount they asked for and went to see the project first-hand.

In Nigeria, cases went from over 700 per year, to fewer than 30 cases annually--all in less than a decade. In fact, as a representative for the Gates Foundation tells me, the country hasn't seen a single case in three years.

This article has been updated with information that wasn't available at the time the documentary was filmed.