If you're a member of AA (as in the Auto Association, not Alcoholics Anonymous!) Disney will give discounts for 10, 15 or 20% on room only. The amount of the discount varies according to the season. It's called TRIPLE A (
AAA) in the US. You just ring up Disney Central Reservations in the U.S. and ask if they have Triple A room discounts for the resort/date you want. You must ensure to show your AA card at check-in.
Mousesavers has info on the AA discounts here:
http://www.mousesavers.com/disneyresorts.html#AAA
Sometimes it's well worth joining AA just to get the discounts. There are also numerous restaurant discounts with AA e.g. some of the Universal restaurants like Hard Rock Cafe.
Oh and it's handy too if your car breaks down.
