Yes, I've cold brewed tea. It took me a long time to try it, because of memories of Mom's pitchers of lipton tea in the refrigerator that I abhored. But when things get hot enough, it's lovely.
One unique issue with the cold brewing is that it locks up a brewing vessel for a long time, so I have to get creative. I have several of these glass mugs that I don't use anymore for hot tea--the slits in the infuser cup clog easily, and they drain too slowly for quick brewing of short infusions. But setting a couple of these up at a time with an inexpensive sencha for drinking 4-8 hours later is very pleasant. Glass infuser tea mug - 3
, on Flickr
And for larger volumes, putting leaves right into a water bottle, covering with water, and putting that into the fridge can be very nice. It may be a bit tricky to drink tea without leaves getting in the way afterwards, though, if not decanted through a strainer into another container.
Biggest thing for me to learn with these cold brew techniques was to not use too much leaf--to use the amount of leaf I'd use to brew up the entire volume of tea in the cold brew vessel, not the amount I'd use for one of several or many infusions in that vessel; and to figure out the right teas to use. I enjoy greens like an inexpensive sencha (one that was just mediocre brewed hot), and various chinese greens and some green/low roast oolongs.