I am not a coffee drinker, but I do enjoy tea. My favorite drink at starbucks is an iced chai tea. I like the spices, especially the cinnamon. Something in the chai tea doesn't like me, though and so I only let myself have one a week.
Second to iced chai, I like the iced passion tea. Unlike black teas, the passion tea is not bitter at all. I usually order it without sweetener.