Toilet Trouble

Put a piece of bubblewrap under the toilet seat so when your victim sits, they are surprised by a loud POP!

You Spilled What

Find an old bottle of nail polish that you don't want anymore. Unscrew the cap and set it sideways on a piece of waxed paper, letting the contents flow out into a puddle. When it dries completely, peel it off of the paper. Now you can put it anywhere and trick someone into thinking there is spilled nail polish. Works best on something your victim cherishes or on one of their important documents!