Unfortunately, this is still very common and we investigate dozens of these a month, usually with the elderly. There are almost always good intentions, but you all know how that works out. Cheryl, while your reply is funny, it doesn't really phase them as they know what the reach of any investigating body is, and according to current US law, any agreement to send funds is purely a civil matter from a local law enforcement stand point. The problem is that once a person willingly agrees to send funds, its a) too late to do anything and a civil agreement.
There may be new legislation coming but the best way to prevent this type of thing is to be aware. The FBI has an excellent fraud page explaining most of the scams.
http://www.fbi.gov/scams-safety/fraud
Lastly, when scammers send out mass emails, the unsubscribe button at the bottom is noting more than a confirmation button that the email address they targeted has a human sitting behind a computer. For those of you whom that's been effective, congrats, you are among the few, and I'd be curious to see how you have your computers set up to see if thats part of the email or part of your security programs. My computer can usually tell the difference between real and scam emails.
I HATE that these scum prey of the elderly or the feeble, and I vigorously prosecute any that are domestic and fall within our jurisdictional boundaries. Please pass along the FBI site to those whom you feel could benefit from it.