How to get a can of beer cold fast?

[cwspellowe]

Salt means the water can stay liquid at lower temps then usual. For example if you stick water in the freezer it will get to 0* Celsius where it will freeze.
However if you was to lower the freezing point by adding salt you will have colder then 0* water! This means your beer will cool down much quicker then if it was sitting at 0*!

Well.. not really. Pure water when it freezes still gets colder, just not in liquid form.

As said already, salt lowers the melting point of the water, so you can have liquid water below 0degC. Doesn't magically make it colder though.