JQuery Image Grid. Example of working code is here: http://www.ragtimelolcat.com/

gistfile1.txt

var imageWidth = 800;
var imageHeight = 450;
var gridWidth = imageWidth/10;
var gridHeight = imageHeight/10;
var halfGWidth = gridWidth/2;
var halfGHeight = gridHeight/2;

$(document).mousemove(function(e){
   if(e.pageX    for(var i = 0; i <= imageWidth ; i = i+gridWidth){
     for(var j = 0; j <= imageHeight ; j = j +gridHeight){
     if(Math.abs(e.pageX-(i-halfGWidth)) var tempY = new String(""+(j-gridHeight)/gridHeight);
      var tempX = new String(""+(i-gridWidth)/gridWidth);
      document.getElementById("image").src="image"+parseInt(tempY+tempX)+".jpg";
     }
     }
    }
   }
});