Você pode adicionar essas linhas ao arquivo /etc/hosts
no seu computador para cortar o acesso a todo o conteúdo do Facebook:
# 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