Another way of getting caught out is from people claiming a sale fell
through and offering the item to the underbidder.  I was offered a
machine once in this way, but luckily had corresponded with the seller
so I knew something was suspicious.  If you are ever offered something
in this way, use the "Ask Seller A Question" link instead of answering
via the email address the offer was sent through.

George Glastris