Xplodar is tiny demo of deformation simulation using Finite Element Modeling (FEM) technique. Done for similarly-named university course. Nothing fancy, just simulates some deforming model and lets you interact with it.
Basically, it's direct implementation of pretty standard stuff: tetrahedral elements, linear shape functions, Green's tensor, explicit integration. All this and more (fracture!) is nicely described in papers like Graphical Modeling and Animation of Brittle Fracture, some nice real-time tailored optimizations are in Real-Time Simulation of Deformation and Fracture of Stiff Materials. You can see that the papers are on fracture, but Xplodar doesn't have one. Oh well, the eternal reason named "lack of time" :)
Zip file here (1MB). Requires DirectX9.0c runtime.
Thumbnails, click for a larger shot.