How should we pay for things in space?
Space has long been the final frontier for human imagination and now it is set to be one ripe for commercialisation.
As space tourism promises to take off it raises the question of how people will pay for goods and services while they are up there.
Click's Spencer Kelly finds out more.
The programme was first broadcast on Saturday 20 July 2013.
Watch more clips on the Click homepage. If you are in the UK you can watch the whole programme on BBC iPlayer.