Have you guys checked out Hansen's "Sparkling Sleek" lineup? It consists of 4 core flavors & 2 green teas, with Sugar Free versions of those also available. I recently tried the
Valencia Orange flavor.
Basically, this seems to be a sparking water line aimed at the same healthy/nutritional market... though it does use cane sugar, so you've got 90 calories there. The classic collection of "no HFCS/preservatives/artificial colors/caffeine" is also played up in the marketing.
Overall, this flavor wasn't too bad. Tasted like bubbly water with a hint of orange... which I guess was the point.

(
Full review if you really, really love bubbly water!)
The other flavors are Blueberry-Pomegranate, Dragonfruit, Cranberry-Grapefruit, Pomegrante Green Tea, and Tangerine Green Tea. I hope to get around to tasting those flavors as well... though sparkling water in a can isn't the most appealing thing in the world.