I think we did out-smart some of the critters though. We painted the ceiling of our porch blue like the sky. Some insects and birds can't tell the difference so they don't light on it...and do their dirty little deeds.
I wasn't sure if there were certain shades of blue that worked better than others, but yesterday a butterfly confirmed it.
He was attracted to the bright colors we painted the house, and would softly beat his wings as he enjoyed his rest there...however, when he got ready to fly away, he kept flying up and bumping his body against the ceiling over and over again. It took him a while to realize that it was not the sky. lol
So apparently that ole southern superstition of painting your porch ceiling blue works just as well to keep varmints away as of haints or spooks. I have not seen a single fly on it yet...or a spook. :)