supercool

A photograph of liquid helium.
WIKIMEDIA COMMONS

When we cool things down, classically, we can think of the atoms moving around inside the material getting slower and slower until they stop moving. That should make really cold things really boring, right? 

“Supercool liquid helium crawls out of containers," Nandini Trivedi said. "And certain supercool metals lose all their resistance. So as substances get cold they start behaving in really unusual ways.”