Bon Odori - an event carried out during the Buddhist festival of the dead, which honors the spirits of one's deceased ancestors. People gather around a wooden tower, and dance in unison to local folk songs and enka classics.
The Marunouchi Ondo Bon Dance Festival in Hibiya Park took place the other day and you can see what went on in the festivities that day.
I love traditional Japan but I hear that some folks prefer the modern. I enjoy both though - how about you?