Last night I went to the baseball game (pictures up on Facebook).  It was a lot of fun, although the team I like, the Chunichi Dragons, lost pretty bad.  Nonetheless it was a good experience.  Japanese fans are nuts and have numerous chants which are led essentially by cheerleaders throughout the fan sections.  The teams chant and sing non-stop while their team is at bat and then rest while their pitcher is on the mound.  How they retain their voices so long, I don't know.