Bogus FBI e-mails related to Nigerian money laundering scam, and what to do about them?

I keep getting e-mails from people claiming to be from the FBI (when clearly they are not, despite their efforts to try and convince me otherwise), insisting that I have a transaction going with a bank in Africa that is involved with money laundering, when I have no transactions with anyone in Africa, or anywhere else in the world for that matter. I would know if I did! Is this just another form of the Nigerian inheritance scam, and if so, what can I do about it? I'm getting so sick of the boatloads of e-mails from these people.