If you live in Iran, you can bypass filter via the following ways:

1- Use https instead of http (not recommended - photos do not show up)

2- Use http://www.new.facebook.com/ OR http://m.facebook.com/ instead of "http://www.facebook.com/" (might be a temporary way and could get blocked later)

3- Use the anti-f i l t e r software such as "freegate" published by "Radio Farda" (Recommended: reliable for a long term use, works fast and needs no setup if you're an "Internet Explorer" user)
you can download this software from following links (same but in 3 different compression formats):

http://www.fileden.com/files/23988/ublck/frgate.rar
http://www.fileden.com/files/23988/ublck/frgate.tar.gz
http://www.fileden.com/files/23988/ublck/frgate.zip

4- Use facebook on the iPhone (Native app can be downloaded via AppStore)!

5- Use "Phproxy" (Firefox add-on) for if you are not a "windows" user!!

6- ... (coming soon!)

Forward this information to all your facebook friends in Iran and help them bypass the f i l t e r.