I learned this from Max at Catalina. It's very simple, but delicious and refreshing, especially in the insane Houston heat this summer. All I do is fill the Chemex up to its "naval" with ice, then brew a pretty light 1/2-pot of drip coffee on top of it. I have a 32oz Chemex, so I brew for 16oz. That's it. Serve over lots of ice, of course. Awesome!