I mean, I've seen movies about this very thing (Godzilla anyone?), but never in person!
This robot's name is Gundam and it is built to scale. Gundam is a popular character here in Japan. I saw several kids with Gundam on their shirts. He is on the edge of Tokyo Bay ahead of a comic convention at the near by Big Site. Apparently that convention will be on the 21st. Gundam will stand his post until the end of August.
It was extremely hot today. In the article I read about it it said says Gundam shoots a cooling spray of mist. If it did, we never felt it. The eyes light up and the head turns from side to side and the robot speaks. I couldn't hear it clearly enough to understand it, but it did get very quiet when the speech started.
To get there, head to Odaiba. Gundam is 18-meters high, so it's pretty hard to miss. If you're coming via the Yurikamome line, get off at the Daiba station.