I made this on the spur of the moment one day at work about five years ago, from a sticky note and a plastic refrigerator magnet of a postal carrier. It was a way of indicating when it would be a good idea to leave me alone.
It's almost always a good idea to leave me alone -- it's just that some days it's an even better idea.
Soon I discovered that many people were taking the Postal Meter seriously. Before dealing with me, they would whisper to someone, "What's it up to today?" Often they decided they could do without my help after all. It can be useful to be thought insane.
POST-CON STATUS
1. Delivering other peoples' mail
2. Muttering & opening other peoples' mail
3. Trashing other peoples' mail and looking shifty
4. Calling in sick & reading Soldier of Fortune
5. Lock & Load ... Duck & Cover ... "Hi, everybody -- I'M BACK!"