When Dennis Tito blasted into space aboard a Russian Soyuz rocket for a seven-day stay at the International Space Station in 2001, he became the first customer of the space tourism industry.
Tito paid an eight-figure sum that some reports put as high as US$20 million ($28 million) for the privilege, so it's hardly surprising that only six tourists have so far followed in his zero-gravity footsteps.
This decade, however, could be a very different story: there are predictions that space tourism could be a US$700 million industry by 2020.
Tickets are on sale now, at US$200,000 a pop, from the ballooning billionaire Sir Richard Branson, whose Virgin Galactic company passed another important milestone in its testing regime this week.
Meanwhile, a range of other entrepreneurs are also piling into this new space race, for the first time convinced there might be some money to be made.
"People grow up just fascinated by space travel," says Will Pomerantz of the X Prize Foundation, which organises competitions to encourage commercial space travel.
"It's loud, it's sexy, and it is in some senses dangerous."
Virgin Galactic has taken around US$45 million in deposits for spaceflight reservations from more than 330 people wanting to get into suborbital space, to see the curvature of the earth and feel the effects of zero gravity.
Branson's six-passenger spacecraft, the VSS Enterprise, will be carried to a height of 15km attached to a mothership, then launched the rest of the way into space.
This week mothership and Enterprise flew to that height together in a maiden test flight.
California-based Xcor, which is developing a two-seater rocket plane to get into suborbital space, signed a deal to export its technology for use in South Korea.
Meanwhile, Armadillo Aerospace, founded by the computer game developer behind Doom, John Cormack, has been working on a craft that will take scientific payloads soon, and humans later.
And in the background somewhere is Jeff Bezos, founder of Amazon, who created Blue Origin and set up a spaceport in west Texas with the aim of manned flight by this year.
His secretive company was silent for two years until re-emerging a few months ago with a US$3.7 million Nasa grant to develop a craft for orbital space flight.
"Virgin is definitely our lead dog in the field," Pomerantz said, "and it certainly has the most publicity and the most visible partners, but we are starting to see others making great leaps and bounds in their ability to fly scientific payloads.
"From a business point of view, you can start flying scientific payloads earlier in the testing regime because, of course, they don't have quite the same safety requirements as people."
There also seems to be competition developing among different states in the US and regions elsewhere in the world for the opportunity of hosting these pioneering space companies.
Virgin Galactic got US$300 million from the state of New Mexico to subsidise Spaceport America in the Mojave desert, and the Government of Abu Dhabi paid US$280 million for a one-third stake in the company and a promise to use the emirate as a hub for travel from the Middle East.
Nasa is showering money, too. Its budget has been slashed and its programme to put a man on Mars has been scrapped, so it is focusing on seeding commercial ventures, and last month offered US$75 million to commercial operators that can put scientific payloads into suborbital space.
The early ticket buyers are most likely paying a premium price to secure their places in the history books.
Observers expect that prices will fall quickly, perhaps to a half or even a quarter within the decade, which should stoke demand.
A 2002 market research report from the consulting firm Futron concluded that, if prices fall significantly, there could be 15,000 suborbital space tourists annually by the end of the decade and, while the technical timelines have slipped, the demand is hardly likely to have: there are plenty more millionaires and billionaires now than there were when the survey was conducted.
In the 49 years since Yuri Gagarin's pioneering flight, 512 people from 38 countries have been to space. The first operational suborbital craft could easily beat that record all on its own.
Now there is just the little matter of proving it's technically possible.
- INDEPENDENTBy Stephen Foley