Answer: Air Defense

If you’ve ever complained about how heavy your work laptop is (and we certainly have more than a few times over the years), know that your chunky business class laptop, no matter how the laptop bag digs into your shoulder, has nothing on the biggest discrete computer system ever built.

The AN/FSQ-7 Combat Direction Central, thankfully just called “Q7” in day-to-day usage, was a collection of Cold-War-era computers built by IBM in the late 1950s for the U.S. Air Force. Each of the machines weighed 250 tons and had two computers. The entire system was comprised of 24 machines linked together to perform radar analysis for the Semi-Automatic Ground Environment (SAGE) air defense network and, collectively, weighed 12 million pounds.