2D physics library, written in C# with XNA.
Following tutorial: http://hub.tutsplus.com/tutorials/how-to-create-a-custom-2d-physics-engine-the-basics-and-impulse-resolution--gamedev-6331 and: http://hub.tutsplus.com/tutorials/how-to-create-a-custom-2d-physics-engine-the-core-engine--gamedev-7493