Customize Your Facebook! Who Unfriend Me?

Facebook Unfriend

Facebook said that there is no feature to know 'who unfriend me?'. But a script can monitor our friend list, so if there is a people unfriend us, the script will tell us. I use this script and works.

First thing that you need is installing Greasemonkey (download here).
Then, go to this site to install the script (just click install on top-right of page)
Finish!