Back when I was in college, I always kept a pitcher of tea in the refrigerator. As a life-long teetotaler, that was my vice
I always got compliments on my tea, and would often have folks stop by just to get some. I scared a few health conscious folks away, though, when they saw how much sugar I put in it

. It never kept them away for long. I usually made a pitcher every day and a half or so, and think I went through 5lbs of sugar a month.
I've made iced tea plenty of different ways, from using a kettle as well as making Sun tea, but really the easiest and IMO the probably the most consistent is to use a normal drip coffee maker.
Again, in college, I had coffee maker for tea only(it was white) and one for coffee(black). I explained the system to my roomates at the beginning of the year, and told them they were free to use both at their leisure(and even use the coffee and tea I bought) but to just not get the two mixed up. The taste of coffee is nearly impossible to get out of a drip pot once it's been used for that, and tea is the same in a coffee pot to some extent. I enjoy both beverages greatly(I probably drink more coffee than tea these days), but their tastes do not complement each other well. I nearly had a fight when I came home one evening to find a fresh pot of coffee in my tea pot! Fortunately a dose of Clorox and a trip through the dishwasher got the coffee taste out of it, and all was well again.