Kombucha seems to be the new "it" drink (although I live in the Bay Area, so this info may be biased). Of doubtful origin, this fermented tea has a passionate following who claim all manner of health benefits for it. I just like it because it tastes good.
Step 1: Obtain Kombucha Starter
You can buy the yeasty starter on the web (sometimes misidentified as a mushroom), or get it from a friend. You might also try looking on message boards of health food stores.
The starter replicates itself in each batch, so one is enough for your lifetime. Soon you'll have enough for everyone you know!