Pond water and bong water have one crucial similarity: you wouldn't want to drink it. Until now, because regardless of what contaminants might be floating around, the LifeStraw Steel filters out more than 99% of the bad stuff.
No batteries you need to remember to charge. No grosss iodized aftertaste. Just dip it and sip directly through its two-stage filter. Assuming you follow its directions and don't expose it to extreme temperatures, you'll be able to drink wherever you find fresh water. (It doesn't filter salt from seawater.)
You can pick up one of these potability pipes for just $55 (with discounts for multiple). Each one's rated to purify 1,000 liters of water throughout its lifetime. And just as cool, as part of their Follow the Liters program, each purchase provides a school year's worth of clean, safe drinking water for a kid in a developing country.
Now you just to convince people it's not for pot.