How can I block all Facebook elements/content

You can add these lines to the file /etc/hosts on your computer to cut off access to all facebook content:

# Block Facebook
127.0.0.1 www.facebook.com
127.0.0.1 facebook.com
127.0.0.1 login.facebook.com
127.0.0.1 www.login.facebook.com
127.0.0.1 fbcdn.net
127.0.0.1 www.fbcdn.net
127.0.0.1 fbcdn.com
127.0.0.1 www.fbcdn.com
127.0.0.1 static.ak.fbcdn.net
127.0.0.1 static.ak.connect.facebook.com
127.0.0.1 connect.facebook.net
127.0.0.1 www.connect.facebook.net
127.0.0.1 apps.facebook.com

Since IPv6 started going live, it has made @mckeed's response incomplete. "::1" is the default feedback loop for IPv6. It needs to be added to each Facebook entry in /etc/hosts. Here's what mine looks like:

# Block Facebook IPv4
127.0.0.1   www.facebook.com
127.0.0.1   facebook.com
127.0.0.1   login.facebook.com
127.0.0.1   www.login.facebook.com
127.0.0.1   fbcdn.net
127.0.0.1   www.fbcdn.net
127.0.0.1   fbcdn.com
127.0.0.1   www.fbcdn.com
127.0.0.1   static.ak.fbcdn.net
127.0.0.1   static.ak.connect.facebook.com
127.0.0.1   connect.facebook.net
127.0.0.1   www.connect.facebook.net
127.0.0.1   apps.facebook.com
# Block Facebook IPv6
::1 www.facebook.com
::1 facebook.com
::1 login.facebook.com
::1 www.login.facebook.com
::1 fbcdn.net
::1 www.fbcdn.net
::1 fbcdn.com
::1 www.fbcdn.com
::1 static.ak.fbcdn.net
::1 static.ak.connect.facebook.com
::1 connect.facebook.net
::1 www.connect.facebook.net
::1 apps.facebook.com