MTek sell an interesting facial armor system called the FAST G3. It is designed to overcome some of the limitations of flip-up riot-style face armor. Thier premium FAST G3A (pictured above) weights 1.5 lbs and provides protection at least as good as the Army Combat Helmet and USMC Light Weight Helmet. The price is $549.99!
[ Many thanks to Paul for emailing me the link. ]