I went to my friend's house the other day and noticed that the inside of her carport was amazingly clean and free of spiderwebs. Then I saw her front and back porches looked the same and figured she had regular professional pest control. No, no, not at all. She had painted the ceilings of all her outdoor structures a sky-blue in order to deter mud daubers and it works for spiders as well. Think it's just an old-wive's tale? Here's the evidence, and an article, there were many to choose from http://goo.gl/nukfXK.