Javascript Hacks.....

Hack 1: Edit the web page.
Go to any web page and type this on address bar and hit enter(return).
javascript:document.body.contentEditable='true'; document.designMode='on'; void 0
You can now edit whatever on the web page.

Hack 2: Flying Images
Go to any web page specially with lots of images and type this on the address bar and hit enter(return).
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)+"px"; DIS.top=(Math.cos(R*y1+i*y2+y3)*y4+y5)+"px"}R++}setInterval('A()',5); void(0);
You can now see the dancing images of the page.

Happy Hacking.... :)