Balance a coloured ball on top of two red balls and the top cushion. State to your friends that your will make the cue ball contact the coloured ball before hitting the reds. Play the cue ball down the table very slowly and aiming centrally at the three balls, before it reaches them give the table a resounding thump. The red balls will part and the coloured ball will drop onto the bed of the table allowing the cue ball to make contact with it.