[nfriedly]

We do something similar only it's posting pictures of ponies to slack.

I also heard of one other company where the tradition was to send an email out to the rest of the company offering to bring in donuts.

[makeitdouble]

The mail thing was a long tradition, until HR stepped in to explain that technically it fitted under taking over a coworker's machine and mail account, and was off bound (e.g. clicking the wrong popup, or auto-completing the mail to the wrong address would turn the joke into more complicated things)