This is just an example:
July 23, 1998 — A certified public accountant and by his own estimation “no dummy,” B.... W..., first heard about the Fortuna Alliance — a promising investment opportunity being advertised on the Internet — from a colleague in April 1996. That same evening, he visited the Web site and read about “a unique mathematical formula” called “The Fibonacci Sequence,” whereby each member could earn up to $5,000 per month, in perpetuity, as soon as he or she had recruited 300 new investors.
REASSURED BY quotes on the site from dozens of satisfied customers and by a 90-day money-back guarantee, he mailed the Web site’s operators a check for just less than $5,000.
Unfortunately for W... and other soon-to-be-dissatisfied customers, the Federal Trade Commission had not yet concluded its investigation of the Fortuna Alliance. The following month, the agency asked a federal court to shut down the site, which it said was advertising a classic pyramid, or “Ponzi,” scheme and to order its operators to pay restitution to investors."
I personally have seen this type of Fibonacci scheme advertised many times on the internet.