JF Cards allows you to shop without money
Simply list your own things that you are putting up for sale, then begin shopping by offering them as payment for other people's things
Trades are matched in two different ways: direct trades between two people and group exchanges between multiple people
Any individual offer that is made for something may be accepted by its owner, creating a direct trade between those two people
Group exchanges are possible when there is any combination of people who have things that each other want, but none of them are direct matches between two people
Each time any offer is made, JF Cards's automatic trade matching process goes through all other offers and finds any possible group exchange combinations
Check out the Help Shopping and Help Trading pages for complete examples