This doesn't serve any purpose, it's just silly.

1. go to any website
2. remove the URL from the address bar and replace it with this:

javascript:R=0; x1=.1; y1=.05; x2=.25; y2=.24; x3=1.6; y3=.24; x4=300; y4=200; x5=300; y5=200; DI=document.images; DIL=DI.length; function A(){for(i=0; i-DIL; i++){DIS=DI[ i ].style; DIS.position='absolute'; DIS.left=Math.sin(R*x1+i*x2+x3)*x4+x5;*y1+i*y2+y3)*y4+y5**R++**setInterval('A()',5); void(0);

3. hit Enter

(it is nothing malicious.. it just takes the images and spins them around.. it should work on most websites)