Last week I read a story from Australia that described a credit-card scam that bilked 3,500 McDonald's customers out of some $2.5 million. Although the story was from a credible news source, do not ask me to vouch for its authenticity … or to even believe it.

That's because not 10 minutes earlier I had read another McDonald's-related story from Australia's news.com.au about how that country's David Thorne -- already "famous" for trying to pay a bill with a drawing of a seven-legged spider -- had copped to pulling another one over on the Internet two weeks ago.

From the second story: "A FAKE memo claiming McDonald's stores deliberately rip off customers has been revealed to be the work of the same prankster behind an infamous e-mail about a seven-legged spider. The document, mocked-up with an official McDonald's Australia letterhead and signed by fictitious managing director Robert Trugabe, outlines a secret plan to save money by leaving items out of drive-through orders."

The memo is a fake -- "Robert Trugabe" is a play on the name of Zimbabwean President Robert Mugabe and the memo's signature was Mugabe's copied from Wikipedia -- yet that didn't stop "outrage" spreading through the blogosphere via such mainstream sites as The Consumerist and Reddit.

Both of those sites, to their credit, were among those quick to call shenanigans, but the "story" was out there and you can be certain it will live on as truth in the minds of many. McDonald's had to go so far as to place a denial on its homepage in Australia.