It has been demonstrated within the past few years that femtosecond lasers are superior tools for microstructuring of nearly all kinds of solid materials. The treated materials suffer no considerable thermal or mechanical damage. This gives access to a variety of new and innovative fields of applications. Periodic structures with reproducible basic patterns, which have a lateral dimension of approximately 10 /spl mu/m, are produced e.g. in nickel and polycarbonate films using a Ti:sapphire laser and a high-precision positioning system.