Today I noticed this sign on a door just outside the psychology building on the CWU campus:
Now, clearly this sign is merely saying "Do not block doorway", but it's fun to think about other possible intentions:
"Do not build a Lego fortress in front of this door"
"Do not hold neighborhood parties in front of this door"
"Do not pretend to block this door"
"Do not deny this door any points"
"Don't mess with Mr. Doorway. Not even sarcastically."