Request for Startups: Water
I don't share a strong sense of optimism that we'll 'beat climate change'.  We need to fundamentally change how humans live on this planet and interact with our ecosystems to move past issues like this.  Projects like these will certainly help a lot of people in the near-term, but I fear they distract us from addressing the real problems.  Sadly, the real problems don't have much of a financial incentive to be solved.