I think it's worth noting in this thread that water in a clear plastic (PET) container left in the sun for 5 hours at 86 F is an effective and recommended treatment. When used with a charcoal filter you'll end up with as good of water as you'll get just about anywhere. While this may not always be an optimal method for backpacking there are certainly times when it can be.

Solar Disinfection


"You want to go where?"