Gorgonz has developed a novel method for keeping hands warm on freezing days - the Exhale line of gloves. When your hands gets cold, you just blow through a small one-way flap to circulate more hot air. Sure beats taking off your gloves to blow into them, carting around battery powered gloves, or going back to the lodge in the middle of a ski day. Via OhGizmo and Googler.
Search for 'gorgonz' at amazon to see the whole line.