SIGMO is a humanoid robot designed to demonstrate the applications of passive dynamics technologies. SIGMO stands for Synthetic, IntelliGent, MObility, and was developed by a team of high school students to demonstrate the capabilities of passive-dynamic actuation techniques. The technology used to enable SIGMO to walk is being applied to advanced prosthetic devices. Current prosthetic devices are nearing the limitations of the available technologies and require advancements such as customized motion, lower cost, and the development of light-weight materials.