In retrospect, it was almost inevitable.
When you rocket people into space, some of them won't want to come down. When you build self sustaining habitats in orbit, they won't have to. The interesting results happen when they save up enough money to buy their own habitat.
Enter the Isaac the Pilgrim. Or Isaac the Welder, as he was known during the early days of the space boom. Isaac was an early adapter; he came up the gravity well to work in space. In those days it wasn't nearly as developed, you had the options of working and sleeping. That suited Isaac just fine; he loved his welding. He'd work sixteen hours straight, take his rest and do it again for the sheer joy of it. In no time flat he's paid off his indenture. But Isaac didn't want to go back down.
Isaac had a repuation at this point; not just hard working but as the best welder in orbit. There are tricks to puddle control in a microgravity environment, tricks to wielding your torch in a spacesuit. Even in directing robots, Isaac was the best. As a free man in orbit, Isaac soon grew wealthy.
But what do you spend your money on in orbit? The entertainment industry had just started up in the floating factories (at least, more legitimate entertainment than vacuum stills and magnetized dice). But you can't sell entertainment to a man who enjoys his work that much. Isaac spent his entire life in orbit, when it came round to retirement age he wasn't going to land back on Earth. Sure there are drugs and therapies for the gravity increase, but those aren't exactly mild and Isaac was a man who loved orbit.
So he bought his own habitat. Previously they had only been available to corporations; nobody else had the money. But by this time we were well along in the space boom, the prices had come down significantly. He got an older model, in need of maintenance. But every spaceman has to know a thing or two about maintaining his habitat, and Isaac was well equipped in that regard.
I don't really know what exactly caused him to quit orbit; the rumor is it had something to do with taxes; the real estate around the Earth can be pretty pricey. But he set off for the moon in a Hohmann Transfer Orbit. From there he set out for Venus, on the Interplanetary Transit Network. Nobody had ever used that path before; it takes years to get from point to point. It's real efficient as long as you're more worried about fuel usage than time. Isaac had all the time in the cosmos.
He was about halfway to Venus before he declared it to be a hermitage; by the time he got there it was a monastay. I guess something in the lonliness of space spoke to his soul. Building from his cramped, one man capsule into a proper habitat took some material, and some labor, but was eminently possible. Spacemen are good at jury rigging, and this structure was never meant to withstand the rigors of an atmosphere. They float from planet to planet, living a lifestyle that would have been recognizeable to any medival monk. They work long hours to maintain their habitat, to keep their lifesupport running, and they spend the rest of their time in prayer.
Currently they're somewhere beyond the orbit of mars, heading towards Jupiter. If you stop by, you'll still see Isaac the Pilgrim's welded message emblazoned over the main airlock:
"The voice of one crying in the wilderness: Make straight the way of the Lord"
This post is mostly me looking for a way to use that transit network. It's a really cool idea, being able to toss things all over the solar system with very little energy involved. The trouble is, it's not going to be very useful; the only time it's practical is when you've got quite a bit more time than fuel. But if you're going to be in orbit already, and if you're already assuming heavy industry up there like I am, then you'll almost never want things that slow. Even if you're shipping in large masses of raw material from the asteroid belt a Hohmnann transfer orbit is going to be a much better compromise. So who would use it? Someone who doesn't care about time at all. And I gotta say, the idea of a monastary in the stars is pretty cool.