Andrew Zolli (again) points out a fantastic project known as the Eastgate building in Harare, Zimbabwe that was modelled on the termite mound (see biomimicry) and that resulted in 10% lower up front capital costs, lower ongoing running costs, and 20% lower rents for its inhabitants compared with the building next door built with a normal HVAC system. (That last bit is an assumption – the article does not explicitly state the next door building’s heating cooling system mechanism.)