A new unheard-of currency called Ecoin claims that they have an AI-powered tool that can detect when a single user tries to sign up with multiple email addresses.  I tried to fool the system, but it caught me!  I used three different email addresses which were nit associated with one another, but I couldn't fool the system.

That seems like a good start for their technology, but for now the only way to earn is via referrals.  Here's my referral link if you want to try it yourself: https://ecoinofficial.org/referral/nmueme0

I'm definitely not investing cash into Ecoin at this time, but I'm watching to see how it develops.