The rankings confirm that Japanese company NEC's Earth Simulator (pictured) is the winner, knocking last year's number one, IBM's Asci White, into second place.
Developed by Japan Marine Science and Technology to make predictions about the future of the Earth's climate and crust, the Earth Simulator is five times faster than last year's winning machine.
Before the Earth Simulator's launch back in April, the US held the top six places in the Supercomputing top 10. Now Japan has trounced its rival but, while this widens the field, Europe isn't even in the running, as its supercomputing industry focuses on developing applications rather than developing the machines.
"The ES is a real challenges for the US Asci programme. The US labs are now falling significantly behind," said Hans Meuer, founder of the top 500 list of world supercomputers, to high performance computing site Primeur.
The Earth Simulator is capable of 35 teraflops (compared to the ASCI's seven), or 25 million, million calculations per second.
Supercomputers are valuable across a number of fields. German car maker Opel, for example, uses an IBM machine to simulate car crashes and the UK's Met Office taps into several supercomputers for data to generate precise weather forecasts.
The full list of the 500 fastest can be seen here.