The BlueGene project at IBM is aimed at making int possible to reach a petaflop speed in numerical calculations.
A petaflop = 1000 teraflops = 1 million gigaflops. A typical PC of today is able to achieve speeds of several gigaflops. One gigaflop roughly means one billion multiplications of 14-digits digit numbers per second.
Having a computer operate at a speed of a petaflop allows one to do many exciting things. For example, allows such things as creating models comparable in complexity with those of a brain (well, perhaps of a brain of a mouse). Therefore, petaflop computing is expected to result in scientific breakthrougs.
The Cyclops64 processor project, formerly known as the BlueGene/C project, resulted in a supercomputer-on-a-chip, that consists of 80 cells. Each cell has CPU-like capabilities, and is able of running 2 individual threads of execution. A single chip can run 160 threads of execution, providing unprecedented parallelism on the level of a single chip.
An earlier project, the Cell processor, was a joint project by several vendors including IBM and Sony, and it was capable of running only 8-10 threads of execution. The Cell processor is known for powering the Playstation 3 game console from Sony.