Free: Contests & Raffles.
•Water filter— A microbiological device that removes bacteria (e.g., Campylobacter jejuni) and protozoan cysts (Giardia lamblia, cryptosporidium) from contaminated water. •Water purifier— A microbiological device that removes bacteria, protozoan cysts and viruses (e.g., hepatitis A) from contaminated water.
Dan check this filter bag out. Katadyn Base Camp Water Filter. This is what we used on our 9 day backcountry hunt in Wyoming this year. Its about the cheapest route to go and is extremely light. Its top rolls up like a dry bag which is basically what it is. You can stuff your clean sock, underwear, camera or anything in it that you dont want wet, then when you get to camp you unload it and fill with 2.6 gallons of water hang in a tree in the shade and have clean filter water to drink and makes a handy wash station as well because the output it slow so you can wash up and not use a ton of water. I personally think this is the absolute best system out there for shear light weight, packability and multitasking with it. Its cool because no one recommended it to me, just kind of stumbled upon it and absolutley love its multiple uses!!!http://www.rei.com/product/737349