Sure no problem, here it is:
it uses maz's euclid car p3d.
the card uses the transparency method plus back-face culling for the one sided card.
to get it looking correct in game. you will need to use the OverideShaderParameters hack on the "question_card_back" shader.
to view it in the editor. make sure back-face is off.
"white_m" is the transparent box surrounding homer's head. i assigned it a blank transparent png file for its texture.. exported to blender you can see the boxes better.
its fun. i think its a similar effect used in the spyro the dragon games, for the portal/gates.
it could be useful for hiding level geometry?