v. To go on another person's social networking profile that has been left on the computer because the victim is away.

To have your Facebook commandeered by a close friend (or foe) for their enjoyment.

to post your own self-promoting information on a FaceBook page under the guise of being a friend or fan.

When someone leaves their Facebook account logged in or shares their login details with someone else at which point someone makes posts to said person's account without their knowledge.

The act of breaking into someone's Facebook account and editing the profile to involve potentially embarrassing or humiliating information.

To masturbate to someone's uploaded pictures on facebook

When someone comments randomly and unintelligent on your Facebook page.