You don't have to be an AP holder to join the Disney Dining Exp., just a FL resident. The DDE is $55 if you are an AP holder, $60 if you're not.
You get a plastic card that entitles you and up to 6 guests, to 20% off of meals & alcohol (yeah baby!) at all sit down restaurants in the Disney parks & in the resorts. The counter service places aren't included. I joined this year & will definitely renew. It has saved me a fortune.
There is info on the official Disney site under FL resident options. If you plan to need it soon, take note that it takes about 2 weeks to get it in the mail.
They also gave me a free spouse card.
Bon Apetit!