The coldest place so far found is the Boomerang (or Bow Tie) Nebula in the constellation of Centaurus.
It has a temperature of -272°C, only 1 degree warmer than absolute zero (the lowest limit for all temperatures). Even the background radiation from the Big Bang is warmer (-270°C).
It is the only object found so far that has a temperature lower than the background radiation.
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Another answer:
The coldest place in the entire universe, so far as we know, is laboratories where research into Bose-Einstein condensates are going on. Temperatures of 500 picokelvins have been reached.
Something in radiative equilibrium with the deepest of deep space would reach about 2.7 K, or 2,700,000,000,000 picokelvins, positively toasty by comparison.
