Didn't look for this topic in past threads so if it's been worn out, I'm sorry!
I played a little first base in college and semi-pro and I would always try to say something to baserunners that started out being relevant, like "nice rip" or "Man, you're fast!" or "I wish our school colors were brown and yellow like yours are."
Then I'd follow it up with some non-sequitur like "Hey, you like dogs?" or "I had the absolute best French fries of my life yesterday." or "Do you have any sisters?"
or this exchange: "Would you rather have ice cream or amatter?"
"What's amatter?"
"Nothing. What's amatter with you?"
Some memorable baserunner replies:
"No, I don't like dogs, but there IS balm in Gilead, you know." (when we played against a religious school).
"Yeah, I have a sister but she's too old for you." So, I answered, "Try me," and the baserunner said, "She's twelve, smart-a$$." (Lewis-Clark State)
and my personal favorite: "What the he** is wrong with you?" (Wazzu).
Feel free to join in.