BJ's is offering a free pint size glass.
Caribou Coffee has a buy one get one free deal - be sure to print the coupon.
Champps Americana - get a free burger with purchase of an entree
Friendly's Icecream - buy one get one free 3 scoop sundae!
IKEA - free breakfast and coffee for dad until 11 - this one is for Charlotte ;)
Marble Slab Creamery - $3 off a 8'' or larger cake
Shoney's - free pancakes for dad!
Spaghetti Warehouse - free 15 layer lasagna or spaghetti meal for dad
TCBY Yogurt free first 10oz yogurt for dad
Denny's send your dad an e-card and get a free pancake puppies sundae for both of you with your entrees (win win situation!)
Another idea is to contact your local zoo or look in your local paper for deals and free admission to local places!