Another think coming vs. another thing coming

The copy editor is in.
I'm presenting occasional posts on the use of English,
not to be pedantic but just for the fun of language.

This is one that bothers me when I see or hear it wrong because the original is so sly and humorous, and the "correction" is so dull.

This is the phrase in use:

"If he thinks he's going to get out of paying for that llama, he's got another think coming!"

Too often lately I see it instead as "If he thinks … he's got another thing coming."

Saying someone has "another think coming" is goofy, but that's the point. The right way to say it would be "another thought coming," of course, which is where the misapprehension begins. People hear "another think" and autocorrect it in their brains to something that's actual English and end up with "another thing."

But "another thing," while a decently grammatical sentence, is vague. What specific "thing" does such a person have coming?

Oh, I know! A think!

Let's save the time on making that bridge and just use the original delightful expression.

What's your take on it? Penny for your thinks.

Feel free to let me know your conundrums or pet peeves.

Photo credit: Johanna Ljungblom