The Large Hadron Collider at the European Organization for Nuclear Reseach (CERN) uses a beam of protons to investigate the most basic nature of the universe. It does this by accelerating the protons to a speed of 0.999999991c; that is 99.9999991% of the speed of light.
Courtesy of CERN
So the people at Sixty Symbols [I highly encourage visits to this site!] asked scientists what would happen if one were to stick a hand into the proton beam.