Baggie of Water

Fact or fiction?
We've tried this, and the results are mixed, but it sounds plausible.

If you put a penny in a baggie of water and hang it in a prime location, it will deter flies. Flies have many facets in their eyes. The way the sun reflects through the baggie and water has a prismatic effect on the fly, confusing it. One explanation says their GPS works on the directionality of the sun, and this throws it off. Another says, that the bag looks like a bee hive, and since they are afraid of bees, they stay away. Either way, it's worth a try next time you're having a BBQ outside. It's better than bug spray any day.

I hope you sleep better now that you know the answer.

Beth's Brain Aerobics

Okay everyone, assume the position (that is pencil or mouse in hand)! Let's work those brains! This will be a regular feature, and I want to hear from you. When I walk in the mornings, I sometimes have strange thoughts that turn into strange questions, which I'll pose to you. These should be exercises in creativity. Think up the most unusual solution and send it to me. No googling to find the "right" answer. I'll post them here!

A couple of RVs in our park have a gallon-size ziplock bag full of water with a penny in it, hanging from their awnings outside their trailer. WHY?

I just found out what this is for, and I'll tell you in a few days. But first, send me your most creative guesses.