Me: Hi, I’m just following up on your call. What did you…

The client interrupts me sharply. 

Client: Look.  I’m DRIVING. I don’t like talking on the phone when I’m driving, DEAR. You’re just going to have to call me back when I’m done.

Me: OK. You have a fantastic day.

Protip: if you don’t want to answer the phone when you’re driving, DON’T PICK UP!