This amazing step by step guide teaches you how to make your own beer with a few simple pieces of equipment and ingredients. From Instructables:
Step 7 Cooling the Wort
Congratulations! At this point you have wort (pronounced wert). Wort is simply unfermented beer. Quicker is better when it comes to cooling. One method for cooling is to create a cold water bath in the sink to partially submerse the brew pot in. Adding ice to the bath will help accelerate the cooling process. Gently swirl the brew pot in the cold bath water. Once the sides of the brew pot become cool to the touch you're ready for the next step but first a word on sanitation.