This is called toilet paper admirer. Very simple. You take a roll of toilet paper. You write a note starting backwards, from the janitor. I'm going to write one to my coworker Harrison. Now, you put the toilet paper back on the roll with the paper going over the top. You roll it up as much as you can until you just see a little tip. Now, if your coworker comes in, and he has a note from the janitor from above.