My girlfriend and I have tried multiple variations of "relationship currency" as I like to call it, but since I'm a shrewd bargainer and she has a tendency to be short sighted (i.e. "I'm tired and don't feel like cooking, I'll give you 500 chore-dollars to go pick up dinner") she eventually ends up with a massive debt and is forced to declare "relationship bankruptcy".
That said, I'm fully intent on doing something like this with my children. Instead of an allowance of some kind, I think kids would learn a lot about the real world if you paid them for doing chores and performing well at school, then docked them accordingly for food, board, rent and expenses.