BIGGEST COMPUTER NETWORK
While the Large Hadron Collider (LHC) has just started its obligatory hibernation period the CERN officially launched LHC Computing Grid (LCG.) Where the LHC is arguably the biggest system ever build the LCG is most probably one of the biggest computer networks ever constructed. But not all the problems in building the LHC could be easily solved with the LCG.

ENGINEER BY SIMULATION
Some problems required massive amounts of compute power and hardly any communication. For this the LHC launched its very successful LHC@Home program. The LHC@Home harnessed thousands of individual computers to simulate the collision of two beams. (Actually the one thing this huge apparatus has been designed to do.) And it successfully influenced the engineering of the LHC.

DIFFERENT GRIDS
While both the LCG and LHC@Home are grids their use is remarkably different. The LCG is specifically designed to handle enormous amounts of data in complex and collaborative computing experiments. LHC@Home was designed to break down difficult problems by brute force simulation. The average of all these simulations is used as starting point for the engineering.

VOLUNTARY PARTICIPATION
But there is another fundamental difference. The LCG is completely build with sponsored tools. Every computer is part of some research facility or directly related to CERN and the LHC project. Participation in LHC@Home is completely voluntary. Just like SETI@Home the participants dedicated their spare cycles to a simulation. But unlike SETI@Home LHC@Home has been successful in its intent.