Gotcha trick
"Performer displays a one gallon paint can, and along with it is a regular paint brush. The brush is inserted into the can and pulled out showing paint on half of the brush, which is set to the side. Suddenly the performer runs out to the crowd or audience and attempts to throw the contents of the paint can into the crowd - What a surprise when all that comes out is a pretty red cloth banner. The performer immediately turns the can around and printed accross the back of the can reads GOTCHA!
"
FAB Magic Company