1993 American Bicycle Comp Lite Beryllium:
…for the astonishing sum of $26,000. The Beryllium bike was made with Beryllium tubing (top, seat, down, seat stays, chain stays) bonded into aluminum lugs. The bike was developed with Electrofusion Corp. in Fremont California. Much of the labor was donated by the company since there was some spare time due to the decline in Cold War business for the company. Beryllium’s atomic number is 4 just after Hydrogen, Helium and Lithium but the specific modulus (stiffness to density ratio) is seven times better than steel, titanium or aluminum, which are all essentially equal. The first frame was overbuilt and weighed 2.5 pounds. Of that, the Beryllium tubing was one pound (including one ounce chain stays), 1.25 pounds of aluminum lugs and 4 ounces of adhesive.
I think only 4 were ever made, and one of those was stolen from the factory.