"Shaking Divs" using CSS

I was quite familiar with the implementation of periodic shake motion of div's using Javascript. But, now that CSS3 is here, implementing shakes of div's has been fairly easier. I didn't knew this was so easy and so efficient using just CSS.

Here's the link to the implementation of the shake:

Demo Link

Its a link of my Github page. The "shaking links" are all dead though, so don't bother clicking them :P
To know how its done, you can go through the source code of the page: Page Source Code

Enjoy!