The phone rang today and I missed catching it. The caller didn't leave a message. That always makes me a little mad.

"What's that number you can dial?" Pär asked me. "The number that, you know, calls back the person who last called you?"

"Star-69," I said. "The verb to describe that is also 'star-69', as in 'I wonder who just called; I'm going to star-69 them and find out.'"

Pär was silent for a moment. "Do you think some geeky engineers out there are giggling away because they chose that number?"

"Oh, I assume it's a coincidence," I said.

"I bet they chose it on purpose," Pär declared. "It makes perfect sense."

"How do you mean?"

"Reciprocal oral action."

And suddenly it did make perfect sense. I never thought of it that way before.