http://www.usatoday.com/story/tech/2013/03/03/facebook-scam-timeline-social-media/1953975/
Q&A: How to avoid Facebook scams? Be a skeptic
Question: I fell for one of those Facebook scams. How do I make sure none of it is left on my Timeline and avoid that kind of mistake in the future?
Answer. This question most recently came from a friend who, in a moment of weakness, tried to claim an alleged offer for two free tickets on Southwest Airlines.
First, this person reported seeing the free-tickets ad on the profile of a trusted friend. A click on that opened a tiny browser window (unnoticed at first) and then copied the same scammy ad to my friend's profile.
It also opened a normal-sized browser window asking for personal information to claim the free tickets; my friend was suspicious enough by then to provide an incorrect birthday and back out after being asked to pay $9.99 a month.