ScienCentralNews: University physicists have created a freezer that can keep ice cream cold using sound waves. They are using a process called thermoacoustics to create a "green" chiller. "Thermoacoustics involves essentially using sound to produce cooling," says Bob Smith, research engineer at the Penn State Applied Research Lab. "It's the interaction between sound and heat." The patented prototype "thermoacoustic chiller," which was put on display at a Ben & Jerry's scoop shop in New York City on Earth Day and successfully kept the ice cream cold, has a container that holds a loudspeaker and a canister of helium... here is a cool flash animation demonstrating how thermoacoustics works.

BTW: Penn State recently launched its yearlong celebration of its sesquicentennial. Take a look back over the past 150 years of the University in this new video.