(ComputerWorld) Congratulations, you won the lottery in a country whose name you can't even pronounce! A wealthy oil executive in a far-off land wants to give you millions of dollars, right now! Sexy girls want to meet you!

Now let's be honest. If someone came to your door and told you any of those things, you'd tell him to get lost. So why do people still fall for this stuff when it's in their e-mail, as if a poorly written message made a weird-sounding pitch any more legitimate?

The saddest part is, the only reason annoying e-mail keeps filling your in-box is because it works. No matter the number of reports detailing e-mail hoaxes gone bad and tales of spammers taking people for all they're worth, people just keep on clicking.  Why? It's the law of percentages. The response rate for snail-mail spam is between 0.5% and 1%. That might not sound like a lot, but if you apply it to e-mail, it means a spammer can send 1 million messages -- without the cost of paper and postage -- and 5,000 to 10,000 people will answer. In fact, a study out this month indicates that nearly 30% of Internet users confessed to purchasing something from spam e-mail.