This trick is a gas! Literally! Imagine bringing a victim/volunteer up to the stage and asking him to have a seat. As the volunteer sits down, the audience hears the passing of gas. You look at the volunteer and ask him to stand up. Lifting up the seat cushion, you remove a deflated whoopee cushion (insert audience laughter here). The volunteer is asked to sit down again, and the eruption of sound from behind happens again (funnier moment). You look awkwardly at the volunteer and ask him to stand up again and lifting the seat cushion, once again, you find nothing.Hmmm?
You say, "It’s okay, everyone is nervous their first time.” You calm the audience from laughter by stating, “Okay, let’s calm down and take care of business.” Turning back to the volunteer, you say, “Have a seat.” And once again, when the volunteer sits, another glorious sound bursts from behind (funniest moment). You say, “I guess you ARE taking care of business! Okay… just let it go.” After the laughter, and after the volunteer stops grinning (or blushing) from ear to ear, you start your trick as you continue on with your next magical feat.
Certainly the Whoopee Seat Cushion is not for every magician or appropriate for every audience. But there are so many possibilities, especially if you get a duplicate ungimmicked cushion for another chair. You can do a "Do-As-I-Do" routine, or have an assistant secretly swap the cushion when the spectator isn't looking, or you can even sit on the cushion yourself, turning this into a self-effacing routine.
If your act is character-based, or if this concept fits your personality or show, and you are performing for the right age, this well-made prop fits any chair and provides a potent prestidigitation with the volunteer!