I have a very small expando from Office Max/Depot/Staples and I have the basic categories that I use the most entered. Everything else goes into misc. I keep my grocery list at the front each week and then pull the coupons I know I'll be using. It's been harder since I am trying to eat more organic food and fresh veggies and they don't seem to offer coupons for those.
The expando is small and works really well. I don't keep coupons for stuff that I wouldn't normally buy, so I don't need a crazy big binder like I've seen some people use. I simply don't use a lot of the products that are in the coupon circulars lately. Kind of frustrating. Plus, I can throw the expando in my glovebox or purse and I never forget it that way. (Along with my reusable produce and grocery bags.)