A funny bet is one that requires someone to perform a trick or activity that is unusual and that is wagered upon by other people, such as having a person can blow a bottle cap, paper napkin or cigarette butt into an empty glass bottle using a straw. The person doing the bet will ask the other person to blow the item into the bottle and the person who is taking the bet will think that it can easily be done.
The bottle cap, cigarette butt or piece of napkin should be folded in half or rolled up to fit around halfway inside the mouth of the bottle. A straw should be positioned next to the item and the person can be asked to blow into the straw to get the item into the bottle. Most people think that this will be easy since the item is already halfway into the mouth of the bottle. The person who takes the bet will lose the bet because the air that is blown into the straw will reach the bottom of the bottle, rebound back toward the top and push air out of the mouth of the bottle. The item falls out of the top of the bottle and will not go into the bottle no matter how hard the straw is blown into.