Below is a recent article taken from EDC The Official Magazine of the LEED Professional:

Duct sealing with aerosol-based technology called Aeroseal could be a cost-effective measure for reducing energy usage in small office buildings. Aeroseal Duct Sealing is designed to tackle duct leaks from the inside out. Aeroseal software allows the technician to accurately measure the duct leakage in residential homes and commercial buildings. The Aeroseal process puts escaping air under pressure and causes polymer particles to stick first to the edges of a leak, then to each other until the leak, as wide as 5/8 of an inch, is closed. www.aeroseal.com

http://www.edcmag.com/articles/94947-aerosol-based-duct-sealing