  We studied the van der Waals interactions of two finite, solid, cylindrical
rods at arbitrary angle and position with respect to each other. An analytic
interpolative formula for the interaction potential energy is constructed,
based on various asymptotic cases. The potential can be readily used for
numerical and analytic description of multi-wall carbon nanotubes, metallic
nanorods, rod-shaped colloids, or any other similar objects with significant
van der Waals interactions.
