The most eye-catching features of these Structures are their electronic, mechanical, optical and chemical characteristics, which open a way to future applications. These properties can even be measured on single Nanotubes. For commercial application, large quantities of purified Nanotubes are needed. CNTs have also proven to be good field emitters and single molecule transistors. The small dimensions, strength and the remarkable physical properties of these structures make them a very unique material with a whole range of promising applications.