The most unique and highly effective fly killer is the Aeroxon Window Fly Killer. These window stickers, in various designs like butterflies or flowers, are mounted on a window pane. Since flies always congregate near a light source, once at the window, they will feed on the Azamethiphos pesticide bait that has been deposited on the surface of the window sticker. This nervous system inhibiting pesticide will kill flies within minutes, depending upon how much they consume, and the pesticide dosage is considered insignificant on its effect on humans. With that, always mount the stickers high up on windows to keep them away from kids and pets, and only handle them with gloves when mounting. They last up to six months, are extremely effective and will rid any household of flies.
For a non-toxic fly killer that will rid your house of flies, the Aspectek Electronic Indoor Insect Killer Zapper won't let you down. The 20 watt black light attracts flies to its electronic grid and then zaps them with an electrical current. Since they are non-toxic and non-poisonous, they can be used virtually anywhere in a house, home, apartment building and around kids and pets alike. Even the electric current flowing through the wires is not dangerous, but caution should be used when handling it, and always make sure it is unplugged before cleaning or moving it. Place it virtually anywhere, from a table top to a swag lamp hook hanging from the ceiling, and let the zapper do the work. A tray catches all dead flies and it removes easily for cleaning.
When in doubt and you want flies killed fast, count on Raid Flying Insect Killer to do the job. Modern Raid flying insect killer formulas are made with the synthetic pyrethrin relatives of Prallethrin and Phenothrin neurotoxins. Although toxic in their own right, the concentrations used to kill flies are not toxic to humans or pets. Nevertheless, do not breathe in the fumes and always vacate the area after spraying. This is a terrific spot spray for killing individual flies on contact. It is so effective that once sprayed, the fly will perish, no ifs, ands or buts. It is very inexpensive to use, and it works best when sprayed directly onto a fly for maximum killing power.
If you want a spray that is naturally based, Prozap Final Fly T made with pyrethrins is a good choice. Pyrethrins are made from Chrysanthemum flowers and are effective at fly control, but they are relatively non-toxic to humans and pets. Of course, always wear gloves when handling Prozap and never breathe in the fumes. This is a spot spray compound that needs to hit the fly to kill it. Since it is a natural compound, it is water soluble and rinses off easily. It comes as a ready-to-use spray or it can also be purchased in bulk and mixed to your own specifications for use in garden sprayers. It is effective, fairly inexpensive, and when used in bulk, it can be a very cost effective spray for barns and out buildings.
If you want the best bang for the buck fly killer on this list, that is non-toxic, safe to use around kids and pests, is humane and cost effective, get an Enoz Flyswatter to do the job. They come in many colors and styles, with the best ones having a metal handle for maximum durability and kinetic energy delivery. Flies have reactions based on air pressure senses and eyesight. Fly swatters are made with holes in the swatting head to fool the fly's air pressure sensors, and coupled with the speed of the swatting motion, means a fly cannot see it coming until it's too late. The design is timeless and effective, and throughout history, more flies have been killed with fly swatters than all other methods combined!