Headed to Japan at the end of the month, must hit spots?

First, this is my second trip to Japan. The first time was in 2009 and I had a blast with my wife doing the normal touristy stuff. This time I’m going for work but I will be taking a few days of leave to spend in Tokyo. Besides Mak Japan, what else should I hit up? I plan on doing quite a bit of shopping :smiley: