The Ray Tracing in One Weekend series of books
Recreation of the classic Grand Theft Auto III game executable
Physically accurate and validated GPU ray-tracer
CIRT - CUDA Interactive Ray Tracer
Realtime raytracer using SIMD on ARM, MIPS, PPC and x86
A toy physically based GPU path tracer (C++/OpenGL/GLSL)
Open-source CUDA/OpenCL speed of light ray-tracer
Gphoton in a simple 3d modeler and ray tracer.
Semi-automatic neurite tracing with tera-bytes of imaging data.
Bruno's RAY Tracing Engine