The Nigerian 419 scam was a typical Nigerian 419 email. The scammer placed the meat of his message about the $14.7 million he would like to share with me in the subject line of his email rather than the body. Im not biting, and I suggest you dont either. Its true that scammers are not that bright, but theyre not always that bright. The scam has failed on this occasion, and youll never be able to bite me again.”]
Source: https://nakedsecurity.sophos.com/2010/03/08/subject-419-scam/