A long time ago, I learned that if you have the option of using paper towels or an air dryer in a public bathroom, your best bet is to go for the paper towels because they "wipe" away more germs. One woman would have us believe that using those air hand dryers will actually make your hands germier!
Nichole Ward did an experiment where she placed a petri dish under an air hand dryer for 3 minutes, and then let the dish incubate for a few days. The results? Various strains of icky bacteria and mold began to grow. Ward says this is because the hand dryer is just blowing dirty, recycled air from the bathroom back onto your hands.
There are still a lot of questions about this experiment; did she use a control petri dish to compare examples? What would a dish that has been wiped with a paper towel from the same bathroom look like under the same circumstances? Even though I think this experiment could have been executed a little more thoroughly, the results are still pretty nasty.