In early 80's research started on carbon nanotubes and other nanomaterials. Nanotechnology was born! Especially the last 10 years or so, you could not read a scientific journal or a newspaper, without being presented another amazing potental application of these materials that would really change the world.
However, until now, almost 30 years after research started, I do not now of any such application in a commercial product, apart from some bulk applications to (slightly) improve material properties.
Somehow, it seems that to me that they got stuck in the "very promising" stadium. It might be that the breakthrough application is just around the corner, and I sure hope it is, after all the millions or billions of dollars spent on their research. Am I just too impatient or pessimistic? What do you think?