http://en.wikipedia.org/wiki/Dot-com_bubbleDot-com bubble
The dot-com bubble (or sometimes IT bubble or Internet bubble) was a speculative bubble covering roughly 1995–2000 (with a climax on March 10, 2000, with the NASDAQ peaking at 5132.52 in intraday trading before closing at 5048.62) during which stock markets in industrialized nations saw their equity value rise rapidly from growth in the more recent Internet sector and related fields. While the latter part was a boom and bust cycle, the Internet boom is sometimes meant to refer to the steady commercial growth of the Internet with the advent of the world wide web, as exemplified by the first release of the Mosaic web browser in 1993, and continuing through the 1990s.
During the mid-to-late 1990s, Cisco Systems, Dell, Intel, and Microsoft were known as "the Four Horsemen of the NASDAQ" because of their dominant market capitalizations. As the bursting of the Internet bubble approached, Cisco Systems, EMC, Sun Microsystems, and Oracle were known as "the Four Horsemen of the Internet."
The period was marked by the founding (and, in many cases, spectacular failure) of a group of new Internet-based companies commonly referred to as dot-coms. Companies were seeing their stock prices shoot up if they simply added an "e-" prefix to their name and/or a ".com" to the end, which one author called "prefix investing".
A combination of rapidly increasing stock prices, market confidence that the companies would turn future profits, individual speculation in stocks, and widely available venture capital created an environment in which many investors were willing to overlook traditional metrics such as P/E ratio in favor of confidence in technological advancements.
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Basically what was going on was a new company called abc.com would get listed with the NASDAQ. Than another new company called xyz.com would get listed. Then the company called abc.com would "purchase", $50 million dollars worth of advertising from the company company called xyz.com. And naturally xyz.com stock would go through the roof. Then soon after that the company called zyz.com would "purchase", $50 million dollars worth of advertising from abc.com and then abc.com stock would go through the roof. But actually no money was ever changing hands between the two companies. But their stock was now worth a lot of money. For a little while anyway. Until the bust.
This is not a complete or exact synopses of everything that was going on back then but I am positive this kind of scam was part of it. I don't think anyone went to jail for this either.
Don