My friend has a parrot... He comes over and says, ""My parrot Chet can sing if I light a match under his foot. See?"" He lights a match under Chet the parrot's right foot and the parrot starts singing Happy Birthday. ""What happens if we light it under his left foot?"" I ask. We do, and he starts singing 100 Bottles of Beer On The Wall. ""What happens if we light it under his balls?"" I ask. We do, and he starts singing, ""Chet's nuts roasting on an open fire...""