Spamming the Spammers

Joshua Gans:

... A few years back I contacted Yahoo and Google with an idea to counter spammers. What if for each spam email that they picked up, they responded — perhaps entering details into phishing forms? This would overwhelm spammers and they would not be able to find ‘legitimate’ responses from the gullible few. That would really alter their returns. Unfortunately, it was explained to me that such a measure would constitute an attack by a US corporation and, apparently, that is against US law. ...