https://arstechnica.com/tech-policy/2021/10/more-than-100000-people-have-had-their-eyes-scanned-for-free-cryptocurrency/

More than 100,000 people have had their eyes scanned in return for a cryptocurrency called Worldcoin, as a project to distribute digital money more widely around the world accelerates.

Worldcoin has distributed about 30 iris-scanning hardware devices, which they call “orbs,” to early users on four continents, who get rewards for signing up more people. Orbs take photos of a user’s eyeballs, creating a unique code that can be used to claim free digital tokens.