I too have heard about the fabric sheets working but have never tried them myself.

I do use and would recommend the Themocell and have noticed very little, if any, vapor coming from it. I have also used a fan and it works if it is strong enough and I can stay in the breeze. I have also tried an electric mosquito eliminator with very little success, we do use Citronella candles when we have company over and they seem to work if you have enough of them but I would not use them around my optics, too much smoke vapor.