Recipe - 1 large linen tea towel, water, ceiling fan or pedestal/desk fan

Method - Dip tea towel in water and wring out excess. Drape over your body (naked works really well, so you may want to try this in private) and turn on the fan. It's necessary to re-wet the towel after a while. I've found this very effective during our heat waves and ensures a more comfortable night when sleeping.