On August 4, 1945, as World War II was winding down and new tensions with the Soviets were starting to wind up, Russian schoolchildren paid a visit to the American Ambassador in Moscow and bestowed upon him a token of good will: a Great Seal of the United States. The Ambassador hung it in his residential study.(…)

Inside the Americans and British found a tiny device the likes of which they’d never seen. So alien was the Great Seal Bug that the only appropriate name for it seemed to be “The Thing,” after the character in the Addams Family (which was then still just a New Yorker cartoon). It was a retroreflector. (…)

“In hindsight,” Ossmann said, “it’s obvious that these types of attacks are practical and employed. For someone who knows a little bit about electronics and a little bit about security, RF retroreflectors should be completely unsurprising. However, I couldn‘t find anyone who had published any research on the subject at all. That was astonishing.“