Zaxby's used to have milkshakes, with 3 flavors: Birthday Cake Batter, Chocolate Cookie, and Banana Pudding. They were caloric beasts, but I've never had a shake from a fast food chain taste so close to actual banana pudding and cake batter. Plus they came in a reusable cup rather than the styrafoam ones.
Somewhat food related, but I also missed when Candystand, Nabiscoworld, and Postopia were still operating. Sure it was thinly veiled marketing to children via flash games, but they were great timekillers, and me and my bro would constantly play the mini golf games.