Smart Mobs and Flash Mobs
A smart mob is a concept introduced by Howard Rheingold in his book Smart Mobs: The Next Social Revolution, and is defined as "group that behaves intelligently or efficiently because of exponentially-increasingly network links." A flash mob, as this web site states, “is a group of people who, usually organized through the Internet, assemble suddenly in a public place, do something unusual, and disperse quickly.” As Suzanne says, flash mobs are usually created via the internet and disappear fast, hence the name "flash" mobs.
Like Courtney, I agree that although these organizations are temporary, they can help the organization that is already established become more productive and sufficient. They can be used just as sufficiently in temporary organizations as traditional organizations. An example like text messaging, a smart mob, could prove helpful to quickly contact another individual and get a reply, no matter how tempoary the organization. In a more traditional setting it helps things run more smoothly by having an almost immediate response from a colleague, without having to report to any hierarchies.