With nothing else to do - Scientists have come up with a new currency designed to be used by inter-planetary travellers.

UK - It is called the Quasi Universal Intergalactic Denomination, or Quid.
It is designed to withstand the stresses of space travel and has no sharp edges or chemicals that could hurt space tourists.
It was designed for the foreign exchange company Travelex by scientists from the National Space Centre and the University of Leicester.
"None of the existing payment systems we use on earth - like cash, credit or debit cards - could be used in space," said Professor George Fraser from the University of Leicester. Full Story - Coins Magazine - Kool Cigarettes - Great American Products