Fruit flies are really stupid. With the exception of that one in the movie "Fruit Fly to Harvard", they are all very dumb and easy to kill.
Lately, I've had a fruit fly problem around my indoor herb garden that I keep in the kitchen. I have 80 zillion tiny flies hovering around my plants! Fruit flies are annoying, but they can also carry disease and bacteria, so I definitely don't want them hanging around my kitchen. Here's how I got rid of them: