My town is small enough, and the people who work here are regular enough, that everyone knows me at least by sight. This is especially true in the post office.
I showed up at the post office today just before they were scheduled to close. I had three small boxes and two large ones. And while I was waiting my turn, one of the postal delivery people called with some kind of emergency and the post-people had to close the office. Sandy's solution to the dilemma of what to do with my un-processed five boxes was to have me leave my stuff and my cell number for them to do when they get back. So I left her a card with my cell number and instructions for shipping and $100 in cash. When they get back to the office and process my boxes, she will call me so that I could stop by for my change and my receipt.
Gotta love small towns sometimes.
ETA: She called and said that Gretchen had an envelope with my receipt/delivery confirmation and cash, and that I could either swing by the office or Gretchen would drop off the envelope at our mutual convenience.