I saw a post on another board about this product, and the guy said it was one of the best pieces of gear to come down the pike in a long time--so with interest raised, I went by Sportsman's Warehouse and picked one up. Cost--$6.99.
While I have not had a chance to use it yet, it looks pretty promising. Filters to 2 microns, so it catches Giardia, Crypto, e.coli, etc, supposedly good for 20 gallons and even has a carbon filter for taste! Anyone else have any experience with one of these??