One trillion calculations, or floating point operations, per second.

The first supercomputer capable of crunching through a thousand trillion mathematical operations every second has been announced by IBM. This is roughly equivalent to the combined processing power of a 2.4-kilometer-high pile of laptop computers.

Blue Gene/P will be capable of a peak performance of 3000 trillion calculations, or floating point operations, per second (three petaflops); but its sustained performance is expected to level out at around one petaflop.