This time of year, bugs can be a real drag. Not only are they annoying—flying around foods and faces—but they can also cause allergic reactions and pass along serious illnesses. Your best defense against bug bites is an effective and long lasting insect repellent. In the past, the term "effective" usually meant a hearty dose of DEET, a powerful chemical developed by the US Army for jungle warfare, which blinds a bug's senses. But it also comes with pretty serious health and environmental worries. Thankfully, there are other potent options these days.