Paste this into your address bar and hit enter.
Code:
javascript:u=['http://img.photobucket.com/albums/v51/Cyberscythe/macros/1202765850087.gif'];i=0;e=document.getElementsByTagName('img');for(var%20j=0;j<e.length;j%2b%2b){e[j].src=u[0];}e=document.getElementsByTagName('iframe');for(var%20j=0;j<e.length;j%2b%2b){e2=document.getElementsByTagName('img');for(var%20j2=0;j2<e2.length;j2%2b%2b){e[j2].src=u[0];}}undefined;