"A scam where the sender requests help in facilitating the transfer of a substantial sum of money, generally in the form of an email. In return, the sender offers a commission, usually in the range of several million dollars. The scammers then request that money be sent to pay for some of the costs associated with the transfer. If money is sent to the scammers, they will either disappear immediately or try to get more money with claims of continued problems with the transfer."
