is clear that a sound understanding of the role of Casimir forces in nano machines will become increasingly important as we learn to manufacture on shorter length scales.

One approach to the calculation of Casimir forces is based on the “Worldline approach” developed by Gies, Klingmüller, Langfeld and Moyaerts [@2002IJMPA..17..966G; @2003hep.th...11168M; @2006JPhA...39.6415G]. While this mostly has been used to study a simplified field theoretic model with massles scalars instead of vector gauge bosons (photons), and nowadays alternative methods are available to directly calculate electrodynamic effects even with frequency-dependent optical properties of materials [@2009arXiv0904.0267R; @2010PhRvA..81a2119M], the worldline approach is interesting for a number of reasons:

-   Due to the probabilistic nature of the method, it is sometimes computationally comparatively cheap (depending on the geometry) to obtain a rough estimate of Casimir forces.

-   With very little effort, the calculation can be modified in such a way that it simultaneously gives all the forces on a number of bodies, making it potentially attractive for problems requiring a geometric shape optimization approach.

-   Finally, it is formulated in a way that is suggestive of a remarkably intuitive interpretation. This may manage to make this conceptually subtle quantum effect somewhat accessible to wider audiences 