It's interesting how many big, hi-tech companies were started by two friends: like Hewlett and Packard, or Google's Larry Page and Sergey Brin. Microsoft was too. Bill Gates co-founded his company - one of the most important and successful in American history - with his high school buddy Paul Allen.
Today, Allen is known more for his mega-yachts and palling around with Brad Pitt and Angelina Jolie than for his revolutionary ideas in the company's early years.
But now Allen has written a memoir called "Idea Man," out this week, in which he not only gives an account of those ideas - he draws a dark portrait of his fellow co-founder and life-long friend.
Microsoft co-founder Paul Allen gives "60 Minutes" a tour of his estate, yacht, space rocket, and, yes - his very own submarine.
Rare footage showing the co-founders of Microsoft like you've never seen them before.
As Allen writes and tells "60 Minutes" correspondent Lesley Stahl - in one of the only in-depth interviews he has ever given - he was too angry and proud to tell Gates point blank, "some days working with you is like being in hell."
"You describe Bill Gates in very harsh terms. You describe him as being quite abusive. I mean, it's not a pretty picture," Stahl pointed out.
"I felt like when I wrote it, I should just tell it like it happened in an unvarnished way, warts and all," Allen said.
"You know, here he is doing such great work. He's almost a saint now. And it seems like an odd time to write an unflattering portrait of him," Stahl remarked.
"The timing had nothing to do with the many wonderful things that Bill has done. But the timing was because I wanted to see if I could do it, and hopefully be alive to see it published," he replied.
No wonder he was concerned: when he started the book in 2009, he had Stage 4 lymphoma. The book goes back to the beginning. When Allen was 15, he met a boy at his private school in Seattle, two years his junior, named Bill Gates.
"Bill and I would actually dive in the dumpsters (at a local computer lab) to try to find listings of the secret inner code of the operating system," Allen told Stahl. "And try to figure out how it worked. That's how passionate we were."
They both became crack coders, but early on Allen emerged as a creative dreamer; Gates, a cold-eyed pragmatist.
"You write that when he was 13 years old, he told you, 'One day we're gonna start a company, run a company,'" Stahl said.
"He was saying, 'Well, imagine what it's like to run a Fortune 500 company.' I'm thinking, 'I have no idea.' You know, my parents were librarians!" Allen replied.
"You kept bringing him ideas. And, you write in the book, 'He was always popping my balloon,'" Stahl quoted.
"That's right. I mean, I would have, you know, ten ideas. And he would kind of pick them apart, one by one. And so then Bill would bring me back down to Earth," Allen remembered.
One of Allen's ideas Gates didn't shoot down would lead to the personal computer revolution and launch Microsoft. It was 1974. Allen was a college dropout working in Boston, and one day he spotted a magazine announcing a new small computer called the "Altair." He ran to show it to his friend Gates, then at Harvard.
"And I said, 'Here, look at the magazine! This is the computer we've been waiting for!'" Allen remembered.
"This is how the PC, the idea that we all have these computers, this is how it started," Stahl remarked.
"Yeah, and it's amazing to think back then nobody had personal computers. I mean, there were computers in universities and research labs and in corporations. But nobody had personal computers," Allen explained.
Produced by Shachar Bar-On