We knew that Elon Musk was working on a roof made of solar panels, and now we know when we'll see them: October 28th, according to a tweet from the real life Tony Stark. Assuming San Francisco's trademark fog doesn't make a surprise appearance too, that is. He says that the SolarCity demo will take place in the Bay area and that we'll also see how the tech integrates with his other projects, the Powerwall 2.0 in-home battery and a Tesla charging system. I'm sensing a theme here...