My favourite used to be Angel Falls Mist, but then I discovered Fruit Cocktail, which is equally as yummy. I've also used Paradiso Peach and Blueberry Skies (sometimes together), and they all make fabulous iced teas.
Here's how I make it:
4 c. water
3 tbsp. tea
2 tbsp. sugar (this was how I used to sweeten it - now I use about 1 tbsp. Saskatoon-flavoured honey)
lots of ice
Bring water to a boil and steep tea for at least 10 minutes (the longer the better.) Add sugar or honey. Fill a pitcher with ice, and pour tea over top, using a strainer to keep out all the loose tea. Pour in a glass and enjoy!