This morning I got received a private message through a social networking site from someone in Abidjan asking me to transfer millions of dollars into my account ...The email, written in all CAPs, is called "Advance Fee Fraud" (AFF), known internationally as "4-1-9" fraud after the section of the Nigerian penal code which addresses fraud schemes. I've received lots of these through my email, but never through messaging on a social networking site. Another reminder to carefully screen your friends.
There's a whole community called 419 Eaters enter into a dialogue with scammers, simply to waste their time and resources. The site is filled examples and even videos is pretty funny.