I found and article on New Scientist that states it is possible for temperatures to drop below absolute zero. The thing is, matter doesn't just behave as if its even colder once it drops below absolute zero, actually the opposite happens. Matter that is below absolute zero in temperature actually has more energy than above absolute zero temperatures.
The really interesting thing is that this has been proven both in theory, and in practice! I imagine plenty of interesting technologies could be developed using such methods.
The original article is here if anyone is interested.
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