WOLFSIM is a Finite-Difference Time-Domain electromagnetic simulator, designed to be easy to use but still very powerful, developed and maintained by researchers at North Carolina State University. It's features include:
-1D, 2D, and 3D structures that are periodic in 1 or 2 dimensions
-Materials that are anisotropic in permittivity and conductivity
-Obliquely incident sources
-Built-in vectorial (i.e. full polarization) near-to-far-field transformation
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B.O.T.S (Bots Tactical Simulation) is a programming game, where players "code" the behaviour of their bot and watch them fight with others bots in a arena. It comes with a full environnement in Java/Swing, for coding, debugging, playing matchs, etc ...