While you can still drive for twenty miles when your gas tank needle hits the "E," you really can't make any more calls once your phone hits one percent. To make sure you still have enough juice for that last drunk dial, get the Devotec Micro Phone Charger . Shaped like a little gas can, this little device holds 220 milliamps to keep you talking for 20 to 30 more minutes, or possibly more if your screen is really dim and WiFi, Bluetooth, Tinder, and LTE are turned off.

Since it's just about the size of a quarter, it's not a bother to have on your keychain so you can whip it out when necessary. Just remember to keep it charged.

Ethan Wolff-Mann is the gear editor for Supercompressor. A Vermont native, he loves biking, running, rock and roll, and words. He keeps his phone brightness really low. Hear him testify on Twitter @ewolffmann.