Pymunk is a easy-to-use pythonic 2d physics library
Creative cellular automata browser game
Library for the numerical simulation of closed as well as open quantum
A simple, physics-based animation library
Cellular Automata library for SUPercomputers (CASUP)
An Open source Analysis and SImulation Toolbox for Fuel Cells
3D simulation library
Multithreaded N-Point Gravity Simulation for PC and Android
Advanced numerical instruments: adaptive meshing, FE methods, solvers
iAIDA is a C++ implementation of the AIDA interfaces.
Box2d Flash Alchemy Port + World Construction Kit