Over on the NOVA website, Peter Tyson speculates about whether there is an opposite to absolute zero:
Seems like an innocent enough question, right? Absolute zero is 0 on the Kelvin scale, or about minus 460 F. You can’t get colder than that; it would be like trying to go south from the South Pole. Is there a corresponding maximum possible temperature?
Well, the answer, depending on which theoretical physicist you ask, is yes, no, or maybe.
(Via Andrew Sullivan.)