Whoopee cushion
A whoopee cushion (also spelled whoopie cushion) is a practical joke device, which simulates the sound of flatulence when sat on. == History and modern usage == Records of a whoopee cushion date back to the 10th-century Aghlabid emir of Ifriqiya, Ziyadat Allah III. He is said to have enjoyed hiding inflated animal bladders under the cushions of his palace for unsuspecting guests to sit on.