Tell us about the last time you made up an excuse in order to end a conversation that was boring you.

Not that long ago someone messaged me a work rant that went on for a few paragraphs.  They apologized for it in the last sentence which was indication their rant was over but I still played it safe.  I made use of the empathetic sentiment while even providing an empathetic excuse.  "I can imagine how tough that must be on you right now.  Sorry but work has gotten really busy...gotta go."

I don't make up excuses.  I just say something like Well, I'm gonna go now and get busy or I'm glad you called; we'll talk again soon.