Mr. Cláudio Furukawa(-sensei), from the physics istitute USP explains how to create a cooling mixture:
You need to mix some ice, some water (2liters x 1), 500gr. salt, and 500cl alcohol.

After you made this mixture you put the beers in it, 3 minutes waiting and it’s done.
Super fast cooling!! will surely test on next party

The original article: Cerveja Gelada