Bitter gourd? Sage? You're far more adventurous drinkers than I am. Excitement for me is a trip to the U.K. so I can hit Sainsbury or Tesco and stock up on Twinings Lemon Twist (can't find it in the U.S., for some reason).

As for the teas we have here in the U.S. (we usually call tisanes "herbal" tea, which is not an accurate description but differentiates it from black tea), I like something called sassafras, which is difficult to find here in NYC. It tastes a bit like root beer, one of the few things I love that I think of as quintessentially American (otherwise, I'm usually a Euro-snob ).