For people interested in fabricating or manufacturing physical things. Including 3D printing & scanning, CNC milling or cutting machines, CAD/CAM software and how we can share ideas between industry and the maker & hackerspace communities.
For there's a large group of people starting hardware startups & projects - look at Kickstarter, Etsy, physical startups, quantified-self, makers, etc. We're all experts in some areas (plastic injection molding), but need help in others (package ...
For professionals and enthusiasts of the discipline of engineering that applies the principles of physics and materials science to the analysis, design, manufacturing, and maintenance of mechanical systems.
For climatologists, meteorologists, statisticians, and other scientists including students that study the science of climate change or work on atmospheric and oceanic global climate models.