Laying siege to the grid

IT IS 2 am in a dimly lit basement somewhere in suburban America. Alone figure illuminated only by the glow of a computer screen taps away at a keyboard. Suddenly he stops, shoots his hands triumphantly in the air and gives a whoop. After weeks of snooping around the internet, eavesdropping on data and planting programs to trap passwords, he has finally done it. He has taken control of one of the most powerful computing resources in the world, a 20-teraflop supercomputing grid, a network of high-powered machines roughly equivalent to the combined power of 20,000 desktop PCs. But as…