You just described the stock market. The only difference is that before, there were only a handful of people with the power and tools to manipulate it (ie. Wall Street), whereas now, due to the power of the Internet and social networks, masses of people are able to coordinate to achieve similar effects.
In a way, what has been happening lately, is the democratization of the power to game the system. Which doesn’t mean that now anyone can do it, but rather that it is not limited only to the rich and powerful anymore (until they figure out a way to gate-keep it again).
