In the US, let's see.. Jolly Ranchers ($0.05 per candy), Gum (5Pc for $0.25), 1 Lb of Bananas ($0.79) [In which case the peel probably weighs in most of it], a few other items.
In Dubai... A large bottle of coke. Three small packets of chips. Two eggs. An apple. There are loads of things available for a buck USD here