Tea rules. Lots of different, interesting flavors, whether you are going for caffeinated or non-caffeinated (or even decaf - I distinguish between tea that originally had caffeine & then it was removed as opposed to the herbals that never would have had it). You can drink it hot or cold. It is good.
Plus, some teas are major power-houses in terms of antioxidants.
I am definitely pro-tea. Hee. (I'm also "pro-tein" if you are what you eat. Ha-ha!) The only downside is that being pro-tea can also make you pro-pee...