These are the rules recommended by the 419 coalition on their website:
1. NEVER pay anything up front for ANY reason.
2. NEVER extend credit for ANY reson.
3. Never do ANYTHING until their checks clears.
4. NEVER expect ANY help from the Nigerian government.
5. NEVER rely on YOUR government to bail you out.

Sounds like great advice to me!

There are a number of other countries, particularly developing countries, where these so called rules apply. Mexico, just south of the border, comes to mind. The only difference is that Nigerian government has a website (if that's true) warning people about it.