Came to say exactly the same thing. I was confused about how the top few posts fit the theme. You could even have a set of tags like #greencompany or #foodsecurity to identify each company's contribution and how tangible it is.
My thought process: 1. Oh - neat idea! [ Checks website ] 2. Okay, cool. Early stages, but on the right track. 3. Who the hell are these companies 4. Ugh, I'm not going to click on each one to find out. 5. Let's go comment about this on HN. I bet someone beat me to the punch.