A couple of weeks ago they did a series on urban agriculture, using skyscrapers basically as giant permaculture & aquaculture facilities as well as offices, and, oh yeah, they mention keeping chickens in urban settings, too! Just about every library has a subscription if you want to get the full-text. Article about urban agriculture The interesting thing about this is that it would contribute to national security and lower oil prices, in that there would be less need for trucking fish, chicken, eggs & veggies all over creation if it's all grown locally, and that cities would be less susceptible to terrorist attacks disrupting the food supply if livestock and produce were farmed in this way. Basically, skyscrapers are mostly covered in glass or at least have oodles of windows. They also have oodles of ductwork to heat them. It is not a very great stretch to retrofit a skyscraper's windows with an extension of a plumbing/sprinkler irrigation system and grow veggies and berries in every window, using aquaculture and permaculture techniques. A big fishtank or three on the lower floors can provide fish waste to fertilize the plants, and as we all know, semi-sad lettuces, garden waste, week-old tomatoes and slightly stale corn can be fed to chickens, who produce more plant fertilizer and eggs. Crops that can't grow in windows/aquaculture can be grown on rooftop gardens, which have been shown to reduce A/C energy costs significantly. The sheer amount of plants in the building would improve air quality. I dunno about the authors' assertions that you could feed most of the office staff with this method. I mean, there's lots of things that should yield X under some theoretical conditions but in reality you don't get nearly as much. Still, I thought this was a really interesting idea. I hope some architects read the article.