MCX is a GPU-accelerated, general-purpose, physically-accurate and feature-rich 3-D light transport simulator. It is one of the fastest simulators because it can use tens of thousands of GPU threads to simulate photons in parallel.
SimThyr is a continuous simulation program for the human pituitary-thyroid feedback control system. Applications of this program cover research, including development of hypotheses, and education of students in biology and medicine, nurses and patients.