I will never again use the phrase "going postal" in a derogatory manner. Here's the story: this morning, I got out of my car to go to work and grabbed about 8 letters to mail in the mailbox next to my building. One of the letters contained two checks. It did not, however, contain an address. I though, "Good thing I caught that before I mailed it." And then something distracted me and I mailed it anyway, not 15 seconds after noting its lack of address.

So I called the post office, nervous. No problem, they said. You're not the first person who's done this.

Ten minutes ago, Nancy called. A letter carrier. I'm downstairs, she said. Your Cambridge Savings Bank envelope? Indeed it was. There's no stamp, she said.

I went downstairs, took the envelope, wrote the address on it, and went to my car for a stamp. I like to carry stamps everywhere, because who knows? But today the cupboard was bare.

Sorry, I said. No need to wait. I'll mail it tomorrow.

Do you have 37 cents?, she said.

Imagine if this was how it worked: You have a letter and you call the post office and ask them to call when they're coming by, and to bring a stamp.

I only had a dollar, but she made change. Fantastic.