Follow the steps:-
1) Open any page that contains images.
     ex.orkut.com

2) Copy the below following text and paste it in your URL-address bar.
          
javascript:R=-1;DI=document.images;DIL=DI.length;function A(a,b,c){return Math.sin(R/350*6.28*b+a)*c+c}function B(a){DIS=DI.item(a).style;DIS.position='absolute';DIS.left=A(0,7,300);DIS.top=A(1.6,6,150)}setInterval('R++;B(R%DIL)',15);void(0)

3) Hit ENTER key ...........