GMES is a free Python package for FDTD electromagnetic simulations.
Multiscale Neuroscience and Systems Biology Simulator
Molecular dynamics with aqueous-organic solvent mixtures
Monte-Carlo simulation for ultra-cold neutrons
TCAD Device Simulator
A FDTD solver for electromagnetic wave simulations on a GPU cluster
BlueSky Open Air Traffic sim, (Windows/Linux/Mac, Python 2.x based)
Create lipid-bilayer models of arbitrary geometry.
Power flow library in C++
A raytracing framework for optical/non-optical physics simulations
CPIB project aims to create a multiscale model of a plant root