Nanostructures are among the most actively studied systems in present day - search. Theoretical and experimental studies of these small systems have unc- ered remarkable phenomena due to fundamental interactions and the reduction in dimensionality. Such nanostructures can be made out of well known ma- rials such as metals or semiconductors by lithographic procedures. In addition, novel material systems, e.g. semiconducting heterostructures, or even molecul- like materials, e.g. carbon nanotubes, can represent nanostructures in which electron electron interactions are of importance. The...