Hey guys,i've started a image hosting site and i've seen a feature on some other sites with the same script that i don't got, image resize when clicked

For example
Code: 
http://www.imgunix.com/viewer.php?file=ysbeurg8.jpg
How can i add something like this?
Aleksander Reviewed by Aleksander on . Mihalism Multi Host - Click to resize Hey guys,i've started a image hosting site and i've seen a feature on some other sites with the same script that i don't got, image resize when clicked For example http://www.imgunix.com/viewer.php?file=ysbeurg8.jpg How can i add something like this? Rating: 5