Mitchell's concept for the future is that "…cities need to be formed based on a faith in the stuff of life, the infrastructure, the things that make a city function." In the past, cities have been formed around religious institutions. Today, the forces of capitalism drive city development. For Joachim, functionality is the new directive.

Waste as Source: Mitchell's Rapid Re(f)use takes one week's worth of e-waste and creates sculptural creatures - in the vein of Pixar's Wall-E - and displays them in a public square in Germany. "It's the best way to get people talking and asking questions," says Joachim. "Is it art, or trash?"

Mitchell's Fab Tree Hab homes challenge the status quo of instant gratification. Although such organic structures might be years in creation, Joachim says: "Seriously, a good scotch takes 12 years. So we have to wait a while…what's the big deal?"

On what it will take for cities to become sustainable and self-sufficient: "The Green Revolution happened. It's done. We won. We have the answers. Now we need to implement the technology that's been created," says Joachim. "Which brings us to the next, more important question: What will it take for society to take notice that we can't keep growing at the current rate without serious repercussions?"

On the Gulf Oil Spill: "…Satan was vomiting crude oil into the ocean," but even that wasn't a big enough crisis to get the public's attention to inspire change. Answering one attendee, Joachim considered the notion that ultimately, it may take financial crisis to motivate change. "We'll need one that hits our pocketbooks."

In response, Dameron asked: "Does technological innovation happen only under duress?"

Joachim: "Not at all. One example is cell phones replacing land lines. Innovation happens when there's a need for a better product, one that works better, looks better and feels better."

In response to another audience member's question about fuel efficiency, Mitchell responded, "Zero efficiency is stupid…it's like No Impact Man. Or Switzerland. What's the point of being neutral? We need positive efficiency - giving back to the environment, not just zero or neutral, but adding something good."

Joachim's propensity for sharing statistics in a stream often verging on the grim is not without a touch of self-deprecation. After noting that "the amount of waste and trash generated in NYC in one hour could fill the Statue of Liberty," he added, "Unfortunately, I'm loaded with these."