Wendy's had the Super Bar when I was a kid. It was like a cross between a salad bar and Old Country Buffet/Ponderosa. There was a "Mexican" section where you could make tacos, an "Italian" section with a couple of different pastas and sauces, and the "Garden Spot" which was a traditional salad bar.
It was weird, but pretty cool for a fast food joint.
Edit: Also there was a dessert section with a soft-serve ice cream machine where you could make sundaes and the like.