Here is a video clip I took in Yokohama a couple of weeks ago. Although I think this sort of clip is already widely available elsewhere on the Internet, it was the first time for me to actually see one of these people in real life.The guy in the video is playing a so-called "beatmania"-game where the goal is to push the right buttons at the right time in sync with music. Some people (like this one) go really overboard and develop their own dance moves as well. Makes me wonder what they could achieve if they actually practiced on a real instrument instead of spending hours at the arcade every day.