If you want a grab-n-go drink instead of the diy drinks I listed, find somehere with Kombucha tea. The GT/Synergy brand tastes awesome. Especially the fruity flavors like the berry ones. Raw and only 30 calories? BRING IT! I also like the sour ones like Ginger, Original, etc but I'm hardcore. I will say, the green one tastes blah.

http://www.tumblr.com/tagged/kombucha-tea