I found this again, thanks to textually.org. I mentioned it here.
Link: textually.org: SMS Guerilla Projector.
The SMS Guerilla Projector is a high powered, home made projection device that can be used to project SMS messages on to buildings, signs or any other surface.
Follow the link to the Troika site and look at their disruptive devices.
That’s so cool. I want one! Make Magazine should do a story on the SMS Guerilla.