Almost everybody gets these "confidential business" proposals, usually claiming to be from Nigeria. Here are three instances (1, 2, 3) that I got on the same day. I had taken to calling this the "money Out of Africa" SCAM, but apparently it is so common that Nigeria's Penal Code has a section about it, so most people call it the "419 SCAM". Here are some resources:
Thanks to Chris Fuhrman (email firstname.lastname, host tfcci.com) who brought this to my attention in a posting to the OpenBSD Advocacy list.