Two more:
- Do not like tweets you post on a forum. By crawling the forum and intersecting the lists of likes, an attacker can find your Twitter account.
- Disable loading of remote content on your webmail or mail client. Do not allow people to use 1-pixel-based trackers to know when and where you read their emails.
"The great secret of happiness in love is to be glad that the other fellow married her." – H.L. Mencken