I swear by Kombucha. Its a fermented tea and its deicious and super good for you at the same time. I bought some of my scoby (symbiotic culture of bacteria and yeast) along to The Waiting Room and taught our rpeservation group how to get started making Kombucha.
For a medium sized preserving jar of Kombucha you need one scoby, a tea cup full of kombucha, 2 tablespoons of black or green tea and a cup of organic raw sugar.
Make the strong black tea in a separate container (a big teapot of something). When this has stewed for 5 minutes or so pour into the preserving jar and combine with the sugar. Wait until this in cool to the touch then add your kombucha and scoby. Taste after a week and if it tastes delicious to you then transfer this into a bottle and seal it and start the above process again. It should taste a bit like apple cidre vinegar. If you leave it longer it will get less sweet and more like vinegar - but this entirely depends on your taste.
If you dont have a scoby you can buy one online (I think this supplier sounds realy good) Or you can make you own. To make you own scoby buy a plain bottle of Kombucha pour some out into a cup and leave covered with a cloth in a warm spot in the kitchen or larder. A whitish film of scoby will start to form on the surface. Once this has thickened up a bit make a sugary tea as above and get started on brewing your own Kombucha.