The most interesting about this project is the feedback of the motors. Knowing the position of the motors is making this very accurate.
Would it be possible to use three color lasers, and create full-color images?
On a second thought, that would probably require variable brightness, or being fast enough so you can move slower on regions you want to appear more bright...
Interesting project, but potentially very dangerous. If you get the laser power wrong then you end up blinding everyone in the room.
Ughh... the language, unreadable.
He has a lot more very interesting projects on his website.