There's always the option to delete your FB account. I went nearly 10 months without logging into FB last year, and doing so made it quite easy to delete my FB account at the beginning of this year.

Regular removal of cookies, and LSO cookies, as well as clearing the browser cache, is also recommended.

Then there's the ubiquitous "Connect" buttons which are spammed all across the web. Prudence dictates that we avoid connecting our logins across the net in an indiscriminate manner.

Finally, there are "burner" email addresses which I use only to register with certain websites. Nearly all of the spam that makes it past my filters is from so-called "legitimate" websites.

Caveat emptor.