How do you improve upon what is arguably the most technologically advanced production car on the market? Easy--make it go faster. When we reviewed thelast year, we were blown away by its arsenal of tech features, including its night-vision camera, preternatural voice-recognition system, and optional massage seats. With the S63, Mercedes keeps all the technoluxury intact and bolts on an AMG-tuned 6.3-liter V-8. The results are...well, .