I received some time ago (don’t remember exactly when, I’ve since deleted that mail) a mail from Tux Games informing me that a mail that I (supposedly) had sent them is being held pending my confirmation that the message is not spam.
Now, I have never ever before heard of Tux Games, so it seems likely that the message being held indeed is spam – and was not, in fact, sent by me. Email source forgery is trivial if you know how the system works, and spammers routinely forge email sender information.
Tux Games is itself engaging in spamming by sending unsolicited confirmation mails to people. I replied to the mail saying so, and asking them to stop doing this. The message bounced.
Today, I received another message from Tux Games. The original message is still in the queue, and has not been read by a human. I am asked to confirm it is not spam. It is tempting to do so.