One of the most powerful supercomputers in the world has now been fully installed and tested at its remote, high altitude site in the Andes of northern Chile. This marks one of the major remaining milestones toward completion of the Atacama Large Millimeter/submillimeter Array (ALMA), the most elaborate ground-based telescope in history. The special-purpose ALMA correlator has over 134 million processors and performs up to 17 quadrillion operations per second, a speed comparable to the fastest general-purpose supercomputer in operation today.