Blue Gold: World Water Wars is a documentary about the increasing scarcity of drinking water. I tried to avoid using bottled water even before watching this. One think that I learned from this film is how "bad" bottled water really is.
There are several ways to obtain this film from its website. However, my preferred method is via bittorrent, accompanied by a donation. And don't worry. Sam Bozzo, the maker of this film, supports this method as well.
I prefer this for two reasons. The version downloaded via bittorrent has no restrictions; you can watch it when you want and how you want. Also, donating directly to the film gives them a much larger percentage of your money.
Here is a trailer.