This is a terrible idea. Something similar to it has been tried dozens of time in the past with disastrous results.
http://object.cato.org/sites/cato.org/files/pubs/pdf/working...
http://object.cato.org/sites/cato.org/files/pubs/pdf/working...
If you think about it, our monetairy system, salaries, social wellfare, taxes. Although not perfect, we kind of have such a system allready :)