A huge number of atomic combinations and arrangements may have useful properties. However, most arrangements won't be useful, or even able to be synthesized. Trying to explore the vast world of potential materials in a lab would be both impractical and just plain impossible. So to map out that enormous number of possible materials, several research groups working on the Materials Genome Initiative are using computers to model known and unknown materials. They mine the resulting data to find areas that deserve a more careful examination.
Via Szabolcs Kósa