That's what we backpackers do to save the planet. We re-use plastic bottles....

Not meaning to hijack this thread, but on our recent trip to the national parks in the Southwest we were VERY impressed with the effort the parks are putting into convincing people to fill up their existing water bottles, rather than buying bottled water. Yes, they were selling reusable water bottles, but I didn't see a lot of bottled water for sale--+and almost NO empty bottles as trash in the parks,!