The human sense of smell isn't that great, and so humans have largely relegated the task of sniffing out items -- non-pungent drugs, hidden bombs, missing people -- to dogs. Dogs are great at what they do, but they pose some issues, as well. For one thing, training bomb-sniffing dogs is expensive. In addition, a dog can alert to something but it can't break down what it smells or give us any details. Bugs though? They may be the solution.