We have daily chores and expected behaviors that earn Mommy Money or get them taken away. (oh the tears!) Then the dollars can be used for buying things...time on tv, time on the wii, or playing a game of their choice with Mom without other sibblings.
Dad was mad it wasn't his face on the Daddy Dollar, but, really, when is he home to dole out the cash for a job well done. Actually the dollars are only given out once a week at our family meeting (the only thing I am actually organized about) when we discuss the details of why they were given and/or taken away.
Mommy Money is great fun - make your own at http://www.festisite.com/money/. But be careful....think ahead how you will feel when you discover your three year old thinks Mommy looks better with a black ink moustache. Hmmm....