Just eleven years ago, the first supercomputer, Intel's ASCI Red, broke the barrier of more than one trillion (short-scale number system) floating point operations per second: one Teraflop/s. Last month, a new system at the Los Alamos National Lab, nicknamed 'Roadrunner', achieved for the first time the staggering result of one Petaflop/s or one quadrillion floating point operations per second. Roadrunner was benchmarked through the Linpack benchmark code, which is used to compare and rank the performance of the 500 fastest supercomputers worldwide (http://www.top500.org). The enormous 1000-fold increase in performance of supercomputers in the last eleven years highlights the dramatic progress of these universal instruments. Supercomputers are the base on which has been built the continuous advancement of computer simulations, now a key element in the scientific and industrial competitiveness of knowledge-based economies in the 21st century. Simulations are the engines for industrial fields such as aeronautics, and the automotive, pharmaceutical, oil and financial industries. They drive progress in key scientific fields of the highest societal relevance, like climatology, fusion energy and biology, not to mention the defence sector with its requirement for reliability testing and maintenance of nuclear weapons without the use of nuclear testing.