1% of purchases made with a Disney Credit Card builds up as bonus dollars, or magic dollars, or whatever they're called. We pay with the card wherever and whenever we can get away with it, instead of cash. Needless to say, this will work
only if you pay your balance in full every month--otherwise you just waste that money in fees and interest. We're working our way towards a Disney cruise at the moment, courtesy of our grocery store, our gas station, the auto mechanic, the odd visit to McDonalds, etc. Now if only we could pay our mortgage off with it, we'd already be booking a stateroom for a Christmas cruise.
In addition to the fees, you also have to keep on top of when the dollars expire--something like three years after the month that you earned them.