I was going to also suggest using coffee ice cubes, it will keep the drink from getting to watered down while your drinking it.
Tips from a
http://www.volcanicacoffee.com/coffee-articles/iced-coffee-recipe.htm
To make a great tasting glass of iced coffee you need to take the same care as you would with hot coffee. Don't try to use leftover coffee for iced coffee but brew it as a delicious drink on its own.
There are two easy methods of preparing iced coffee
Iced Coffee over Ice Cubes
Brew extra strength coffee using 1 tablespoon to 4 oz. of water
Pour over ice cubes
Add sugar or cream if desired
Note: The extra strength coffee is important so that when the iced melts it does not dilute the coffee.
Iced Coffee with Ice Coffee Cubes
Brew regular strength coffee and freeze it in ice cube trays
Fill glasses with the coffee cubes and pour regular strength coffee over them
Add sugar or cream if desired