In the April issue of Vanity Fair, David Kirkpatrick shares a rarity: an in-depth look at the man who created Twitter, Jack Dorsey. Dorsey – who was ousted as CEO of Twitter in 2010, but still remains a Chairman – is much like you’d expect: a man overflowing with ideas.

His newest one, called Square, is a device that people can attach to their phones that then allows them to accept credit card payments. It’s (once again) a potentially game-changing idea – essentially allowing the smallest business owner the ability to accept payments quickly and easily.

But that’s not even the most interesting part of the profile of an interesting man. Some highlights from the piece include Dorsey admitting how much it hurts to not be a day-to-day presence at Twitter, him saying that he hopes to be mayor here one day (Bloomberg told him to raise a ton of money first), and there’s this funny anecdote about the first version of what would eventually become Twitter:

That evening, he wrote some code that enabled him to have an e-mail re-posted to as many people as he wanted. He entered the e-mail addresses of five friends into the software, and took a walk in Golden Gate Park. In an e-mail’s subject line he wrote, ‘I’m at the Bison Paddock watching the bison.’

His friends weren’t impressed. ‘I quickly learned that, first, no one else had a mobile e-mail device, so the system was kind of useless,’ Dorsey says. ‘And secondly, no one really cared what I was doing in the park.’

Well, people sure do care now.