Casimir zero-point radiation pressure

We analyze some consequences of the Casimir-type zero-point radiation pressure. These include macroscopic vacuum forces on a metallic layer in between a dielectric medium and an inert [epsilon(omega)=1] one. Ways to control the sign of these forces, based on dielectric properties of the media, are thus suggested. Finally, the large positive Casimir pressure, due to surface plasmons on thin metallic layers, is evaluated and discussed.