The Home Soda Maker starter kit runs $219.99 and includes the machine itself, two glass carafes, and two big bottles of CO2 which should provide you with about 120 bottles of carbonated water. There’s also the “Plus Package” which costs $269.99 and includes one extra bottle of CO2.
You can use the machine to simply make fizzy water, but the real fun starts when you mix in various flavors. These “SodaMix” bottles cost $5 each and make 12 liters. Aside from soda flavors, you can buy mixes to make flavored water and tonic as well.
wiinterr's comment: Yikes! A penguin needs to stick to buying her soda at the store!