It's not a magic trick, but a beautiful visual gag!
Throughout your act, a small camp stool sits on the stage. It can be used to hold small props, or just as a piece of stage setting. When you finish your last effect, almost as an afterthought, walk over to the stool, step on it and Wowsers! The stool jumps almost three feet in the air! What a visual!
People will come back after the show just to see the stool jump. I know, because it happens to me all the time. Dazzle 'em with some great magic, but when they come back after the show, they ask to see the stool. After all, how many times have they seen jumping furniture?
The Jumping Stool is made from sturdy tubular steel, so It will hold up to any abuse you can give it. Folds flat to fit in your case.
A great prop for the MC or comedy magician!