A rubber band refrigerator

In above video Ben Krasnow builds a refrigerator using rubber bands as the cooling element. Of course it doesn't provide a lot of cooling, but a thermal imagining camera shows that it does slightly lower the temperature of the chamber. Ben explains the physics behind it all.

Ben's YouTube channel, Applied Science, is well worth a visit. he has a lot of fascinating projects, including a DIY scanning electron microscope, that are all pretty amazing.