If you have food allergies, you know what a terrifying gamble it can be when you go to a restaurant. An allergen like peanuts, eggs, or nuts can be enough to ruin your day if you ingest just a little. For people that have severe allergies, ingesting just a little can be serious enough to warrant a trip to the hospital. Scientists at Harvard Medical School know that food allergies are increasing around the world. That’s why they’re working on iEAT, a portable food allergen detector that only costs $40 to make.