Movimento com Jquery

Script de movimento simples com teclas de coordenadas.
$(document).ready(function() {
$(document).keydown(function(key) {
switch(parseInt(key.which,10)) {
// Left arrow key pressed
case 37:
$('img').animate({left: "-=10px"}, 'fast');
break;
// Up Arrow Pressed
case 38:
// Put our code here
$('img').animate({top: "-=10px"}, 'fast');
break;
// Right Arrow Pressed
case 39:
// Put our code here
$('img').animate({left: "+=10px"}, 'fast');
break;
// Down Array Pressed
case 40:
// Put our code here
$('img').animate({top: "+=10px"}, 'fast');
break;
}
});
});