I was surprised to see crooks using Craig's List, too, Jerry. I posted some things a month or so ago, and am still getting e-mails from people trying to sell me one goofy thing or another (quick weight loss, get rich quick while sitting at home, etc.).
Another one is ClassMate.com, which keeps sending me messages like:
Remember Mark Spravale?
Newest Class of ’74 Alum
Uh... no, I don't remember him.
or
So-and-So just signed your book....
Then I'm supposed to pay some money in order to see who this person is. And if I want to communicate with him, I have to pay more money.