GridPP is a collaboration of particle physicists and computer scientists from the UK and CERN. They have built a distributed computing Grid across the UK for particle physicists. At the moment there is a working particle physics Grid across 17 UK institutions.
With the Large Hadron Collider, the world's largest particle accelerator, running at CERN the Grid is being used to process the accompanying data deluge. The UK Grid is contributing more than the equivalent of 20,000 PCs to this worldwide effort.