Absolute zero sounds like an unbreachable limit beyond which it is impossible to explore. In fact there is a weird realm of negative temperatures that not only exists in theory, but has also proved accessible in practice. An improved way of getting there, outlined last week, could reveal new states of matter...
Creating negative-temperature systems to see what other "bizarro world" properties they might have is tricky. It is certainly not done by cooling an object down to absolute zero. It is, however, possible to leap straight from positive to negative absolute temperatures.
There's more at
New Scientist, but I don't understand any of it, so you'll need to explore it on your own.
