I used to work in a pizza place where we had a couple pretty crazy ones
Buffalo Chicken - Sauce is Frank's Red Hot mixed with Ranch instead. Chicken marinaded in Frank's Red Hot
Breakfast Pizza - White Gravy for sauce, mozzarella and cheddar cheese, green peppers, sausage, bacon, tater tots, onions, scrambled eggs cooked separately then sprinkled on top.
I'm quite partial to the classic BBQ Chicken pizza though. In India once I got a Chicken Tikka Masala pizza from Dominos, it was so dank.