I always, always have peppermint and chamomile tea on hand, as these are my hot drinks of choice at night. I also always have Earl Grey or Lady Grey (which I'm starting to prefer, I like the additional citrusy-ness). Those are my day-time teas. I'm not actually a very adventurous tea-drinker, and I don't tend to like fancy, fruity teas or even spiced black teas. I do keep some roobius, Celestial Seasonings Bengal Spice (I think it's called) and decaf green for when people come for a visit, but I never drink those myself.
For my Earl or Lady Grey teas I drink Twinings, and for Chamomile I drink Celestial Seasonings Sleepy Time. Otherwise, I have no brand loyalty, but I'm open to suggestions! Especially for a really good spiced black tea :)