Hot water does freeze faster than cold water
in certain circumstances.

If you have two containers made of conducting material - metal is good - and fill one with hot water and one with cold, then place them in the freezer, the one containing the hot water will freeze first.

This is because of two reasons. Firstly, the hot water melts the ice in the freezer below the beaker, and thus gives better thermal contact so heat is lost more quickly. Secondly, there are convection currents present in the hot water which mix it efficiently as it's cooling, therefore presenting a fresh surface to the cold air and cold sides in the beaker.

The net result is that the hot water cools not only more quickly, but more uniformly than the cold water, and although the cold water will start to freeze more quickly, the (previously) hot water will freeze completely first.

New Scientist ran experiments on this subject a while back. Obviously there are conditions - if you do it with water at 99°C and 0.1°C the cold water is likely to freeze first, but tap water (65°C and 20°C) shows the effect described. And it helps if the shelf in the freezer is solid, so as to carry away the heat more quickly. But it is a real effect.
( K2k6 has a proper job these days, Tue 29 Jul 2008, 14:37, Reply)