h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

These items are also known as cotton-buds, or in the U.S. as Q-tips.
When I was five I pierced my sisters ear drum with one of these and I don't use them anymore.
Doctors always tell you never to use them on your ears, because they only drive wax further into the canal rather than making your hearing any better.

There are as far as I am aware two useful applications for cotton buds, which are outside the beautifying realm and sanctioned by the medical profession (if indeed they know about them)

1. To make an audience for Pod Racing in Star Wars.
I recently watched a program on the special effects used in the new Star Wars film, The Phantom Menace. In this you would expect to find lots of computers, but a surprise was waiting at the end of the program. They created a whole audience by dipping cotton wool buds in different colour dyes and put stuck them on a model of a bandstand. I never knew cwb's could be so versatile and this convincing as an excited racing audience.

2. To clean a head on your tape deck, save on those nasty soundless tapes
Look for a small rubber wheel when you open the tape deck. (It should at the bottom or at the top of the tape compartment, where- ever the bottom of the tape is slotted in.)
Take a cwb and dip it into any kind of clear alcohol, easiest is vodka or lighter fluid, otherwise just get some at the chemist.
Turn the little wheel with your finger or something else small, like a toothpick (gently) and wipe away the dirt on the head with the intoxicated cotton wool bud. There you go, your tapes will be happier and your tapes & tape recorder will live longer.