![dek](https://content.time.com/time/2004/inventions/inventions/cuts/120297.jpg)
Environmentally Safe Ice Cream Freezer
Inventor: Steven Garrett
Availability: Prototype only
To Learn More: benjerry.com
When ice cream maker Ben & Jerry's asked a Penn State scientist to build a freezer that won't contribute to global warming, the result was like a frat-house experiment gone right. The apparatus uses sound waves to compress and expand helium, which in turn chills a liquid cooling agentin this case, vodka. Bizarre, but it works: the stainless-steel canister was used last April to cool pints of Cherry Garcia and Chunky Monkey at a New York City scoop shop.