Those electric sound producing "Scare off the females" zappers have been around for years . They are IMO as effective as those razor blade sharpeners they actually sold in Europe (little plastic pyramid aligned with the moon or some such rubbish).
I find the best is to use those inexpensive green coils that you light and then blow out the flame. Probably does wonders for the lungs, but at least seems to keep most of the mozzies away
