For Firefox users, may I recommend ShareMeNot (http://sharemenot.cs.washington.edu/). It also nukes the tracking behavior of Twitter, LinkedIn, StumbleUpon, Digg, and Google +1.

Or, if you are an Adblock Plus user and want to kill Facebook on non-Facebook sites, add the following rule:

  ||facebook.*$domain=~facebook.com|~127.0.0.1