Additional information about Chaff:

Chaff is used as a defensive weapon. Chaff is made of hairlike strands of aluminum cut to several exact lengths. The different sizes of the aluminum strands correspond to a particular frequency of tracking RADAR. By combining different sets of stranded aluminum, you can confuse a wide variety of RADAR-guided missiles.

To deploy the chaff, a small explosive is used to expel the strands out of a sealed container. In the Navy, these charges are called squibs. Squibs are electrically fired. This creates a large cloud of chaff, which creates a huge target for the RADAR-guided missile. The aircraft will fly a pattern to minimize the missile getting a lucky hit as it goes through the cloud. After the missile is past the cloud, it continues on its way, looking for a target which should now be behind the missile. It flies off and crashes when the fuel is expended.

Other uses for chaff:

This stuff is worse than fiberglass. If you really want to screw someone over, put a tiny bit on their bed. It will give them a rash, and it is exceptionally itchy.

Another form of chaff (ok, I'm showing my age here) came from old teletype machines that had paper tape capabilities. The tiny circles of paper that were punched out of the tape were the best form of confetti you could get. Dump a little on someone, it stayed all day, sometimes two. A sprinkle in their hair would require hours to pick out.

Ummm... not that I ever did these :P