Couldn't find a "mail fraud" category, so "con artist" will have to do.
Larry Hourd sends you a very official-looking document saying that you've won between one and two million dollars. He doesn't say just WHERE you won it, and this lack of specific information should set off alarm bell #1. After going through all sorts of gibberish, the real "bottom line" is that he wants you to send him about $13.00, plus your credit card account numbers.
Now, if you've got a million coming, why can't the thirteen bucks be deducted from that? Alarm bell #2.
And, what could they possibly need your credit card account numbers for? Alarm bell #3.
If you get one of these, just turn it over to your local FBI. Since it's a scam based in America, and involves mail fraud, it falls under their jurisdiction.
Remember, you CANNOT win a "contest" you never entered, and there is NO FREE LUNCH!