A possible explanation for the strange hot engine/cold water thread:
If you observe a water droplet on a hot surface, say the gas burners
of your stove, you see the droplet dancing for a while and only 
slowly evaporating, altough the burner is darn hot. 
What happens is the following: the water immediately vaporizes on
the hot surface, naturally. This vapor layer however forms a pretty
good insulation since now there is an additional heat transfer 
between the vapor and the liquid. Moreover, the liquid locks the
vapor underneath on the surface. This actually leads to an insulation
as long as liquid water is on the hot surface.
Note that you don't have this problem with very small droplets, ie.
mist, since then the entire droplet vaporizes and evaporates off the
surface immediately. Jens.
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|     " You just said something very profound. "                      |
|                                         Bela Lugosi, The Raven      |
|                                                                     |
|       Jens-Dominik Mueller, University of Michigan, Ann Arbor       |
|                        muller@engin.umich.edu                       |
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