Key Points

>Tech millionaire Sam Altman's new start-up Worldcoin uses orb-shaped devices to scan people's eyes in exchange for free cryptocurrency.

>The company has so far amassed over 100,000 users globally already, and aims to hit the 1 billion user milestone by 2023.

>Worldcoin CEO Alex Blania hinted Worldcoin could be used as "infrastructure" for a universal basic income one day.

It sounds like something out of a sci-fi movie — metallic orbs that scan people's eyes to pay them in digital currency.

That's what tech investor Sam Altman has been working on for his new start-up, a company called Worldcoin. Launched out of "stealth" on Thursday, Worldcoin promises to hand out free cryptocurrency to people who verify their accounts by taking an iris scan.