What to Do: Coca-Cola Bottling Tour
If you are staying a bit longer than most in Tokyo, Coke has a pretty cool tour and again, it is free.
You'll see a short film in English, get a free Coke and be guided around the bottling plant, seeing way-cool machines filling bottles and capping caps. It all takes about 90 minutes. You do need to call in advance (0424-71-1415), and be sure to ask for directions, as it is a bit outside of downtown. The closest train station is Kiyose on the Seibu-Ikebukuro line.