I have seen those "fly keep away-ers" all over here in Texas, mainly at restaurants, but they don't have pennies in'em, just water. I think the shine when the sun hits it is what you are looking for.
As far as fruit fly traps, those truly do work great. The "recipe" i found online was as follows;
1) use a cut up piece of fruit or leftover apple core, the sweeter the fruit the better, place in a shallow bowl or container.
2) fill the bottom of the container with vinegar, apple cider, red wine or whatever you have in your pantry, don't fill all the way up over the fruit ( you want the flies to "smell" the sweetness in the fruit), just fill until bottom is covered and then a little more, this will be were the flies fall in and die.
3) put plastic wrap over the top, straight, with no wrinkles in the plastic, secure with either rubberband or tape.
4( cut slits in plastic wrap, small enough for the flies to get in, but not to large, then they will escape and continue to pester you, I just use the tip of my chefs knife.
Place on the counter were flies are abundant, I even had one over by my stove, even though my fruit is on the other side of the kitchen and the flies found it and went in.
