I was studying for chemistry and in my textbook they had a little thing about liquidmetal. It has a similar molecular structure to glass but instead of silica it is composed of metals (a mixture of titanium, zirconium, nickel, beryllium and copper). On this site:http://www.liquidmetal.com/index/ they say it is stronger than titanium, but a lot more elastic, so it might make quite a springy feeling frame, but strong, and light. Who knows. Anyone have a spare few million bucks?