My first 5-boxing team was Paladin, Holy Priest, Shadow Priest, Warlock and Mage.

It was BC days and dungeons were tough.. I haven't tried a completely mixed group again since. I have mixed up my paladin, shaman, mages, dks and priests for boosting and JP gains - but it was all trivial content - geared level 85s and an 81 taking on Blackrock Caverns.

I wouldn't mind giving it another go, but I'll need the heirlooms and that can take some time.