Wikipedia takes the fun out of everything…
From the wikipedia article on rubber bands:
Rubber bands can be used as projectiles. The easiest way of doing this is to place one end on the thumb or index finger and stretch the other with the opposite hand. When the latter end is let go, the band will release. Rubber band guns also exist to fire rubber bands, and are generally more accurate. Rubber bands sting if shot at point-blank range against bare skin, but are generally harmless. However, it is best to avoid firing them at another person’s face or eyes, bare skin, or at close range. As projectiles, rubber bands are sometimes used in intra-office or school pranks, involving employees or students with many dozens of rubber bands being shot at or between other various employees or students.
Yeah but the rest of the web makes it fun again. Curious how many rubber bands it makes to take you happy - http://www.therubberband.info/happy.php