I receive lots of emails from National Geographic green list, local greeny orgs, etc. One email promoted a product called "Soda Club." The Soda Club is a home seltzer and soda machine. The biggest benefit that I see, aside from a money savings - about which I'm still skeptical, is the green aspect.
My husband Dan and I drink tons of soda water, seltzer, carbonated water. While we recycle these bottles, their life is pretty short. With Soda Club, we'll be able to reuse our bottles at home and work. That ultimately means less waste. And less production of plastic means less burning of fossil fuels, less chance of plastic contaminating the water stream and so on.
So I urge you to check out Soda Club. My friend Kelly is a proud owner and also can attest to the joy it's brought to her life ;)