That sounds like a cool product- let me know when you locate it!  Except, is the lit part so large that it takes away from the property?

Around the holidays, there is a similar product that projects an image onto the side of a building.  Perhaps you could modify one of those.  I remember seeing them as a child, but I think our town passed an ordinance against them long ago.  Or perhaps they don't like rain.  We don't have billboards here and we have strict sign laws.  I think I'd also be concerned about causing a distraction - like an accident!