There is an old powerplant or steamplant bulding in Philadelphia. You can see it, just to the right of the new Amtrack building as you exit the city on Vine street heading out to the Schuykill Expressway, going West to King of Prussia.

I've seen old buildings like this converted into nifty office, store and business spaces. This one has an enormous smokestack - maybe 150 feet tall, or more. Very grand and impressive. It would be a shame if it were simply knocked down...

I got to thinking - chimneys and smokestacks are capable of creating a very strong updraft - it is their purpose in life! I'm wondering if these stacks could be used to produce a low-cost ventilation system. Somehow that natural draft could be harnessed and possibly provide great air condition or supplimental cooling to an office or workspace. Yet another reason to save such an old building.