There appears to be a pervasive fruit fly attack on Toronto's houses. Here is how to take it to the little guys like you really mean it:
1. Find a cup that you don't want to use ever ever again. Label it or somehow identify that no-one should use it. I find it helps to put little threatening symbols on the side.
2. Put a little bit of sweet-ish alcohol in the bottom.
3. Place some fruit, vegetable, or meat (if you can stand it) that is past due in the cup.
4. Cover the mouth of the cup with saran wrap. Wrap a rubber band around the mouth of the cup to secure the saran wrap if necessary.
5. Use a fork to poke some holes in the saran wrap.
6. Clear the area of all food (put it in the fridge, empty the garbage, wipe down all surfaces).
7. Set out your custom fruit fly death traps.
8. Laugh maniacally.
The little guys will fly in through the holes, attracted to the only available food source in the bottom of the cup, then won't be able to fly out.