  We introduce an efficient technique for computing Casimir energies and forces
between objects of arbitrarily complex 3D geometries. In contrast to other
recently developed methods, our technique easily handles non-spheroidal,
non-axisymmetric objects and objects with sharp corners. Using our new
technique, we obtain the first predictions of Casimir interactions in a number
of experimentally relevant geometries, including crossed cylinders and
tetrahedral nanoparticles.
