In Nature today there is a short report on a new anti-reflective coating made from silicon nanorods. It is said to be 10 times more effective than current anti-reflective coatings, and could make the blackest opaque objects yet produced.
http://www.nature.com/news/2007/0702...070226-11.html
It will be interesting to see if and when this might hit the market.
Al.
