What Type of water do you give your animals?

This is mostly for non fish owners, (nothing personal ) Though I wouldn't mind hearing some fish related opinions, as water is obviously a special concern there.

I know there is even "pet water" being sold now, which is more expensive than most bottled water. I operate under the theory that if I won't drink it, I'm not giving it to any of my animals. And my tap water leaves allot to be desired. I have been using purchased filtered water (reverse osmosis/uv sterilization), from the machines that have become common in the front of grocery stores here in the states. I have allot of animals, and I go through allot of water, and it runs $1.75/5 gallons on average. Hopefully I can get a good reverse osmosis system on my house at some point, and be done with it. What does everyone here use?

You can choose more than one option, if you use more than one type, or if you use something other than tap water, but would use tap water if you lived somewhere with better quality water.