Hydrogen

Diamond Surface Data Storage based on hydrogen or fluorine terminated carbon atoms being the bits.

Molecular Surgery on C₆₀
Ron Dagani explains, "Molecular surgeons have chemically opened a hole in the C60 cage and inserted a helium atom or a hydrogen molecule into the cavity. In so doing, they have demonstrated the most efficient route developed thus far to place guest atoms inside a fullerene cage [Angew. Chem. Int. Ed., 40, 1543 (2001)]."

If you are aware of another use for this element in nanotechnology, please post it in the Nanotechnology Forum so that we can discuss adding it here.