Joking aside, In southern Italy in September, where the bastards bite hard and long, I find 50% deet totally effective as long as you cover yourself properly with it. I also find that those plug-in jobs you put In your bedroom work well. Christ knows what you're breathing in all night though. Craghoppers shirts and shorts have a built-in mozzie repellent that doesn't wash out, and I never get bitten through those clothes, only on my bare bits.