Facebook has a 42-foot by 42-foot QR code on top of its Menlo Park office that’s apparently visible from space—and ready-made to communicate with aliens (who probably use QR codes far more than us humans! Amirite?!). It’s not the first time we’ve tried to communicate with ETs! Other times: the Heliotrope, a parabolic mirror, SETI, and that time scientists beamed a Beatles song far into space. Behold! A gallery!