IBM has regained its position at the top of the Top500 Supercomputer Web site list, effectively ending NEC's nearly unchallenged three year reign. IBM's "BlueGene/L" has inched past NEC's Earth Simulator by a margin of 0.15 teraflops. What's more, Big Blue claims that BlueGene/L occupies one hundredth of the space and consumes one twenty-eighth of the energy that is required by the dethroned Earth Simulator.

Today's reigning supercomputers -- manufactured by IBM and NEC -- achieve a whopping 36.01 and 35.86 teraflops, respectively. In comparison to today's technology, CRAY 1, the word's first supercomputer, sustained a top speed of 133 megaflops.

A megaflop is equivalent to one million instructions per second; a single teraflop is equivalent to a trillion operations per second.

Big Blue's besting of NEC is just the beginning of a much more ambitious goal: to build a 130,000 CPU model for the Lawrence Livermore National Laboratory capable of exceeding 150 teraflops per second. This second, more powerful machine is likely to be ready early next year, and is sure to shake up the Top500 List.

The BlueGene/L supercomputer was derived from work that began in 2003 which resulted in IBM's "Teraflop in a box" prototype. Both machines are used for studies in hydrodynamics, quantum chemistry, molecular dynamics, climate modeling and financial modeling.

Earlier this summer IBM scored another high-profile government contract. Big Blue was drafted by the United States Navy to deploy an ultra-scale high performance computing (HPC) system that will become the fastest supercomputer in the US military's arsenal. This system will operate at a peak speed of 20 trillion mathematical operations per second.