Pretty much, ArtOfLosingMFZB. They manage to not lose money because they make you charge a minimum for each item and then they take that minimum. You can add extra on to make some money yourself if you wish, although obviously this makes it slightly more unlikely that people'll buy them if you get carried away.
They make them to order, so unless somebody buys them they're never made. It's a pretty good system if you're after some unique stuff and have a knack for design.