Michel J. Anders was looking to implement a better Voronoi Noise in Blender Cycles. The voronoi noise in Blender Cycles is a bit limited, being based solely on the distance to the nearest point.
While Blender’s voronoi noise can create a variety of patterns, to get a true wider array of patterns, you need to expand it a bit. Michel notes that this can easily be done with the Open Shading Language (OSL). The problem lies with OSL’s implementation in Blender is limited to the CPU.
So Michel decided to implement the Voronoi Noise in the Blender source code. Check out Michel J. Anders’ adventures into creating a faster GPU driven Voronoi Noise for Blender Cycles here.