Some common life-saving medicines, such as insulin, are made of proteins so large and fragile that they need to be injected instead of ingested as pills. But a new generation of medicine -- made from smaller, more durable proteins known as peptides -- is on its way. In a quick, informative talk, molecular engineer and TED Fellow Christopher Bahl explains how he's using computational design to create powerful peptides that could one day neutralize the flu, protect against botulism poisoning and even stop cancer cells from growing.