image grid fading mask-- is it possible?

[Caramelo]

how can i the grid fading effect on an image depending on where you rollover it, which would then reveal an underlying image? i've included a link that illustrates an example of the problem. help!
http://www.stilismo.com/question.htm

[whispers]

Create your "GRID" image (photoshop maybe....cut it into the pieces that you want it to fade out in (ie: 1'x1' squares) then on rollover that image fades out. Hope this helps..or gives you some ideas. -whispers-