Carbon Fiber Feet
Oscar Pistorius is a sprinter. He's also a double-amputee; he runs on carbon fiber legs. You might think this is a huge disadvantage but the International Association of Athletics Federations just declared him ineligible to compete in qualifying events for the Beijing Olympics. A German sports scientist compared the energy efficiency of his spring-powered legs to the standard ankles-and-feet arrangement and concluded his prosthetics give him a–ahem–leg up.
We'll be a little sad if we don't get to see a double-amputee run alongside other Olympians, but the controversy surrounding Oscar's case illustrates a larger point: prosthetics are getting really good. This is positive news. Now we just have to fix that healthcare problem so these advances are available to people who need them.