"Forget heat — ­drying laundry is about cranking up the volume," said Jamie Condliffe at Technology Review. Researchers at the Oak Ridge National Laboratory in Tennessee have built an energy-efficient clothes dryer that blasts laundry with high-frequency sound waves. The machine uses ultrasound to vibrate water droplets out of fabric, forming a fine mist that's siphoned out like a regular dryer.

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Oak Ridge's ultrasonic dryer can dry a medium-size load in 20 minutes, compared with 50 for a conventional machine. It also uses 70 percent less energy than conventional dryers, which are infamous energy hogs. The typical household dryer uses more power over the course of a year than a refrigerator, dishwasher, and clothes washer combined. The project was developed in collaboration with GE Appliances, which plans to eventually use the technology in its own dryers.