Hi, how are you? Doing anything fun for the weekend? Uh, hang on...
What? I'm not talking to _you_!
What? I'm not talking to _you_!
They hunch over slightly, and exaggerate the act of speaking into it... visually emphasizing that they're not just casually strolling along talking to themselves.
I know when I'm listening to comedy audio podcasts and can't help laughing, I make sure I'm holding an in-ear bud in place in my ear, or looking at the blank screen of my phone.
We're a silly lot.