Being weight conscious since before I hit puberty, I'm something of an aficionado of zero-calorie and low-calorie drinks. When a new one comes out, I get super excited!
Enter low-calorie Snapple Juice Drink.
A particular subset of the "juice drink" brand is marketed for health benefits- currently they have two flavors (Noni Berry and Kiwi Pear) that boost metabolism, and two (Peach Mangosteen and Goji Punch) that boost immunity.
I've tried the two "metabolism boosting" ones. An entire bottle of the stuff has only 20 calories and 2 grams of sugar. The Kiwi Pear one is a little bland, the Noni Berry one tastes really, really good and I find myself buying it pretty frequently. I definitely enjoy it more than other Snapple products I've had (all of their Diet Iced Tea flavors, although to be fair, almost of all those have zero calories).
It's only 5% juice and has no vitamins or anything, and I really couldn't tell you if it boosts your metabolism or not, but it tastes good and has very little sugar, and it's a unique flavor, too (the Noni Berry, that is).
I've also tried their Diet Green Tea Asian Pear, which is from a different product line. Smells pretty, but tastes like lightly flavored water. It's also supposed to boost your metabolism- again, I can't tell you how true that is.
Overall I'll give these new products , because I think they're trying a little to hard to be indie and hip, and because the stuff is pricey, and the only good flavor was the Noni Berry. If I could buy these in bulk at a lower price the rating would be higher, but I've only seen these sold individually.