The latest Kickstarter project, looking for crowd funding, is a little different to most - a space elevator to be built on the moon.
The Liftport Group says it plans to start small, and has already raised the money for the first stage of its plans. At a cost of just $8,000, it intends to launch a robot on a tether attached to a balloon two kilometers up, breaking its previous record by half a kilometer.
The next stage, says the company, will be to make an even higher one, to as high as three kilometers. This will mean dealing with the effects of sub-zero temperatures on equipment.
Building the real thing, though, will cost rather more - as much as $800 million, says Liftport.
A space elevator, or orbital tower, would be able to lift cargo cheaply and easily to orbit. A cable, probably made from carbon nanotubes, would stretch from the surface up to a geostationary orbit - and beyond, to create a counterweight keeping the whole thing stable.
As one 'elevator car' goes up, another descends, recovering a lot of the energy used.
"Once the Lunar Elevator is fully functioning, astronauts and equipment will be able to soft-land cargo on the lunar surface. Compared to flying the Space Shuttle, humankind will be able to travel 1,000 times farther for one-tenth the price," says the company.
"Using our models, we believe we can build a LSEI [Lunar Space Elevator Infrastructure] that can transport three dozen people to the Moon per year, before this decade is out."
Liftport's long had ambitions to build a space elevator on Earth; but the moon would make for a much easier location. There's less gravity, meaning that the cable wouldn't need to be as long, and less atmosphere - as well as a lot less politics.
Last year, Japanese construction company Obayashi announced plans to build a space elevator on Earth by 2050. The firm says it hopes that the terminal station could house tourists as well as a laboratory.