How about whitening gum?I buy mine direct from China. I'm suprised no one has mentioned Oolong, as it is my favorite. It's typically the type of tea served in Chinese food restaurants. It is quite tasty, and there is a wide range of tastes between the different varities and regions.
I don't like tea in teabags - I prefer to use loose leaf tea and brew it in a teapot designed for accepting loose leaf. While at work, they have a small container that will hold your loose leaf tea and you set it on top of a regular paper cup from your office, and just add some hot water from the water cooler and you've got it at work, too.
I also like green tea, and then I go to a store called teavana occasionally to pick up some matevana/roobios blend which is incredible, as well as a few others they have.
But by far I like oolong. Only trouble, I like to drink it daily (though I don't each day) and so I have to keep some Crest Whitestrips on hand as it seems to stain my teeth a bit after months of use. But the whitestrips clear it back up...