In Key Largo you have to run from your house to your car or a literal cloud will descend. They have a truck and a plane that sprays noxious gas made with diesel fuel across the island every day but it does no good. It was fun watching Jahovah's Witnesses run around slapping themselves though.
I believe there is a Mosquito repellent for the pocket pcs, so clams my little brother has one for his Palm Tungsten E squared. Haven't tried it yet, but want to test it lately. :)
there is also the high-frequency-sound-adaptor thingy that you plug in one of your room's electric socket. turns out mosquitos can't stand them, but too bad my pet dogs can't stand it also (damn you k-9 superhearing) most people say it works too... so poopsicles...
well, mosquitoes doesn't seem to be attracted by the ol' blue light zapper thingy. they do like the ones that emit CO2, emit fake body heat, or even low-frequency fake heart thump sounds. (which explains why humans are prime targets) but those kind of machines are very very expensive.