In February of 2011 WSID blocked Facebook more harder than ever, blocking the iPod app and even www.www.facebook.com
So to get around this big block this time, install this extension on a computer OTHER THAN COMPUTERS IN THE COMPUTER SCIENCE LAB(blocked on those computers, but none others? :/) then just go to facebook.com
and it will not be blocked.
This is a method that can not be blocked by WSID unless they block SSL completely, which when some countries did that there were riots, so doubt that would happen.
What this extension does is defaults your connection to Facebook to SSL always. Will also make it immune to web filters unless SSL is disabled entirely.