I am planning an outdoor show very similar to this. I belive it is would be quite possible to achieve affects like this with the Wii system and Smoothboard or other drawing software.  For best effect you would just want to use a very powerful projector. Instead of a lazer pointer just place your Wiimote right on top of your projector so the the beam of the projector and the beam of your Wiimote camera are as close to being on the same line as possible. Then THE SHADOW cast by your IR pen as you stand say five feet in front of the projector, should be properly aligned to be able to calibrate and draw. Another way might be to use Smoothboard in "presenter" mode and somehow get a stationary IR LED source, probably a very bright one, close to the wall that you would like to draw on.  I will post videos of my own efforts once I get this done, say 2 or 3 months from now. This would be awesome!! a really great way to get the word out about the wii mote system and maybe open up a whole new market of IR pens and IR stationary sources, i.e. D.J.s and ravers will have to have it after they see it.

IR lasers are expensive and quite hazardous. As the lasers emit the electromagnetic radiation which is above the visible light range, it can cause damage to the eye as the reflex response of closing the eye is only for visible light.

Red laser or Green laser may be a better choice.

Regards,
Boon Jin