So, I broke down and got the SodaStream, home soda maker, recently.
It's about 50 cents worth of plastic and a dollar's worth of metal that attaches to a CO2 can and adds carbonation to the water. I thought it would be a money-saver, but it turns out to be much more of a toy. It is undoubtedly better for the planet than my buying bottles of Pellegrino, though.
I haven't purchased fuzzy water since I bought the machine, but I have spent $70 on the machine, $10 on a refill CO2 can and $20 on flavorings (there's fruit essence flavors that I can have in addition to all the heavily sweetened soda flavorings).
I think it's going to take a few months to recoup my costs.