From one of my new favorite blogs, Brain Stimulant:

Graphics Processing Units (GPU) are commonly used to power video game software. However, they are also finding use for a more diverse array of scientific research as well. A GPU conference has recently taken place discussing some of the applications of this technology (see PDF 8.1 MB). Here are a few excerpts about the GPU brain projects. One deals with the connectome (circuit diagram).

Determining the detailed connections in brain circuits is a fundamental unsolved problem in neuroscience. Understanding this circuitry will enable brain scientists to confirm or refute existing models, develop new ones, and come closer to an understanding of how the brain works. Prof. Jeff Lichtman and Center for Brain Science (CBS) at Harvard launched the Connectome Project three years ago to determine the complete, detailed wiring diagrams of neural circuits from sequential high-resolution images of the central nervous system using electron microscopy (EM). These high-resolution, large-scale EM datasets pose very challenging computational problems for 3D segmentation and visualization in terms of developing suitable algorithms, coping with the ever-increasing data sizes, and maintaining interactive performance

Connectome Project entry is on page 58 of the GTC Program Guide.