In recent years a variety of stochastic particle tracking methods have been proposed, developed and compared for efficient numerical mass transfer computations in the engineering literature. Particle tracking microscopy is also an essential method of observation of heterogeneous protein diffusion in cellular biology. In this talk a particular stochastic particle method recently proposed and and shown to be superior in laboratory tests is explained as an unexpected byproduct of our earlier work on dispersion rates. This is based on a recent paper with B. Chastenet, J. Ramirez, E. Thomann, and B. Wood.