Swarming. Imagine unmanned aerial vehicles blotting out the sky, obliterating anything that moves, and injecting terror into every observer's heart. Impossible? Maybe not. The aerospace research community is working hard at developing UAV control technology that requires as little human supervision as possible, and concepts using swarms are receiving serious attention. Swarming is not just a scare tactic, but also a viable control technology for multiple autonomous vehicles that system designers can use. Swarming itself is a type of emergent behavior, a behavior that isn't explicitly programmed, but results as the natural interaction of multiple entities. Swarms used correctly could be terribly effective, but used the wrong way could be as vulnerable as gnats to Raid(Trademark). This paper looks at what the author considers swarming to be, how you get it, what it might be (and might not be) good for, and the questions we need to answer on the way forward to evaluate and implement it.