Or maybe don't. You're hammering the servers of the poor folks at rawgithub.com, who specifically asked that their service not be used for heavy traffic situations.

thanks, it worked after several refreshes. I could've checked network panel in chrome to see what's up if I was smart enough.

It is actually quite cool, I tried similar thing (albeit a trivial approach) with css only: http://cssdesk.com/VYN67

Try changing image url in source to see different effect.