I would say that the current "hot" item with regards to filtering is the Sawyer Squeeze. It weighs 3 oz, filters to 0.1 microns, and costs around $50-60. And, with the right attachments, can be attached directly to a bladder to suck out water through the filter. In fact, after writing all this, I realized Sawyer already makes one....
Sawyer water filter
I am not saying you shouldn't try. I am just saying, if you do, then it needs to have a better filter, at a better price.
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