The TSA won't let you board some flights unless your devices turn on

You know how airport security will occasionally ask you to turn on a phone or laptop to prove that it isn't hiding explosives? Well, that's no longer just a rare inconvenience -- if you take certain flights, it's mandatory. The TSA now requires that you power on your gadgets when flying to the US from "certain overseas airports." If you have a dead battery, you're out of luck. You'll likely have to leave that hardware behind, and you might go through "additional screening" at the same time:

As the traveling public knows, all electronic devices are screened by security officers. During the security examination, officers may also ask that owners power up some devices, including cell phones. Powerless devices will not be permitted onboard the aircraft. The traveler may also undergo additional screening.