Free: Contests & Raffles.
I bought one for the high hunt last year. Its good for drinking out of but not for sharing, cooking,etc. Also for the high hunt it was heavier than what i would choose to carry.
http://www.cabelas.com/product/Camping/Survival-Navigation/Water-Purification|/pc/104795280/c/104774580/sc/104324580/Katadyn-Pocket-Water-Microfilter/727430.uts?destination=%2Fcatalog%2Fbrowse%2Fcamping-survival-navigation-water-purification%2F_%2FN-1100737%2FNs-CATEGORY_SEQ_104324580%3FWTz_l%3DSBC%253BMMcat104795280%253Bcat104774580&WTz_l=SBC%3BMMcat104795280%3Bcat104774580%3Bcat10432458013,000 gallons. How many seasons will it take me to drink that much water?
I have never used a filter before and I have hunted in a lot of states and a lot of different places in those states. That being said I got a Sawyer Squeeze filter for xmas so I might start using it. Not very heavy, and it looks like you can use it as an inline on a hydration bladder, gravity filter, or squeeze filter. Pretty versatile.