An attempt to produce a supercomputer by wiring together hundreds of desktops and laptops has fallen short.
The aim was to see if PCs could be used to generate the power of supercomputers at a fraction of the cost.
But a network created by researchers and students at the University of San Francisco failed to make it into the ranks of the world's 500 fastest computers.
Despite the setback, the organisers of the event declared it a success.
"This proves that this kind of computing can be competitive with computers that cost tens of millions of dollars," said graduate student John Witchel.
Supercomputers are used to tackle complex problems, such as modelling biological process and their cost can run into $100m.
The world's fastest computer is the Earth Simulator, created by NEC in Yokohama, Japan, dedicated to climate modelling and simulating seismic activity.
The organisers of Saturday's event in San Francisco had hoped to produce about 500 gigaflops of power, the equivalent of 500 billion sums per second.
In the end the 600 volunteers who took part in the experiment only managed to generate 180 gigaflops by hooking up hundreds of desktops and laptops.
The failure to make it into the list of the world's top 500 supercomputers did not dishearten the organisers of the experiment, dubbed Flashmob 1.
"Flashmob is about democratising supercomputing," said Mr Witchel. "It's about giving supercomputing power to the people so that we can decide how we want supercomputers to be used."
The term flashmob is used to describe spontaneous crowds summoned up via the internet to take part in a form of performance art.
Last year, Virginia Tech built one of the world's fastest supercomputers by wiring together 1,100 Apple G5 computers. BBC News