https://www.thiswebsitewillselfdestruct.com/

A project that I found at the start of the COVID lockdowns. It's a website where you anonymously type stuff, and can read messages from others without any possibility of interacting or commenting. If it doesn't receive a message for a full day it will delete everything. 

Besides the fact that it's strangely comforting to write a message there, it also induces a strong feeling of futility when you read other's messages: They get very personal sometimes, and I've found some messages that I really empathized with; in some cases i may even have been able to help them with their problems. But there's no way to reach the writer and one day the message will be gone forever.