Polar Seltzer. I am obsessed. It's produced in Worcester, MA and is distributed throughout New England and to several other mid-atlantic states, however, I am having trouble finding it in the Big Apple. I grew up in Massachusetts and didn't think anything of it when I'd buy a few 12-packs of my favorite flavors. In fact, at my local Big Y grocery store, they were usually "buy 1 get 2 free" or some other crazy deal like that. Sadly, I couldn't find it anywhere when I moved to DC back in 2001, so whenever friends or family would visit, they'd drive down several cases for me (thank you!) to replenish my stock. Now that I'm in New York, I figured I'm a step closer to home and I should be able to have frequent access to it, but I am still on the hunt.
Seltzer is a great alternative to soda, fake juices or even to water if you're feeling bored with it. I like bubbles and Polar's flavors are great. My faves are Black Cherry and Cranberry Lime. At zero calories, zero sodium, zero fat, zero sugar, zero everything, it's a perfect nutritious choice.
Poland Springs also makes a great seltzer that is zero sodium (and zero everything else) too. There are many other good brands of seltzer, but beware of those seltzer brands that have sodium added to them.