369 mail

You're referring to the "369 mail" phenomenon!

The "369 mail" refers to a peculiar trend where people are sending mail with the address "369" instead of their actual address. This phenomenon started on social media platforms like Twitter and Reddit, where people would share photos of envelopes with the address "369" and claim that they received responses or packages at this address.

The reason behind this trend is unclear, but some theories suggest that it might be a form of social experiment or a way to test the limits of postal services. Others believe that it's simply a fun and creative way to play with the concept of mail and addresses.

It's worth noting that sending mail to "369" is not a practical or effective way to communicate, as it's unlikely that the postal service will be able to deliver the mail to the intended recipient. However, the "369 mail" phenomenon has become a popular meme and a symbol of the power of social media to create and spread unusual trends.