To keep flies away - Fill a zip lock bag with water and 5 or 6 pennies and hang it in the problem area - apparently, it keeps flies and wasps away. Some say that wasps and flies mistake the bag for some other insect nest and are threatened.
Do Water Filled Zip-Lock Bags with Added Pennies Keep Flies Away?
www.decadentdaylilies.com says This does work I tried it a few nights ago, it takes all of around 15 seconds to work, add water to the bar of soap and rub it on to where you have been bit by mosquitos.
Check out this free mosquito repellant app! All you do is turn up your phone's volume, adjust the frequency so that it's out of the human hearing range, and sit back as ultrasonic sound waves trick mosquitoes into thinking that bats are coming in for the kill. Free | thisoldhouse.com
Keep this in mind if you start seeing lots of spiders around your place. Natural spider killer or preventer... take one cup of vingar, one cup of pepper, a teaspoon of oil and liquid soap. Put it into a spray bottle and spray along the outside of your outside door and along windows; refresh after it rains.