Indoor fly traps ?
Here is a link that gives you information on how to do this.
Use a bottle that has a narrow neck, enough for the fly to crawl in and deep enough for it to be unable to fly out of. Put something sweet at the bottom and maybe some water, and that should do the trick...............
Great article from Betty! I take it 1 step further with fruit flies. I have the sticky traps from Walmart, they come in a pack of 5-6, the ones for catching mice. Take a trap, peel off the protective paper and leave it unfolded-just flat and then put a piece of decaying sweet fruit on it in the center. The fruit flies will land and stay put.