My buddy showed me this and I'm sure this can be spun into a routine.

Make a bet with a girl. Give her three tries. Bend a bottle cap in half. Place it part way in an empty bottle that's on its side on the edge of the bar. Tell her she can't touch the bottle and needs to blow it in. Sounds stupid on your part but she will not be able to blow this stupid bent cap into the side ways bottle. The physics of it is the air blown goes around the cap, hits the back of the bottle, and then comes back and pushes the cap out of the bottle.

Now make a seperate bet. You can blow it into the bottle. After she felt so stupid about not being able to blow it in she will love to see you suffer at it. Pull out a straw and blow right where the the bend on the cap is. You never said you couldn't use a straw. After you slowly blow it you are triumphant.

You can use this against anyone you want to win a bar bet with. Happy sarging folks