While exploring the history of "hippie punching", I came across this passage:
One day when I was but a young boy, I was walking down the street with my dad to the hardware store. He suddenly stopped, crossed the street and punched a man. When he returned, I ask, "Father, why did you punch that man?"
He turned to me and said, "That's a stupid question." Then he punched me.
It was a stupid question, because who my dad punched was a hippie. Back then, everyone knew that you punched hippies, but I've noticed that this knowledge may not be being passed on to the next generation. [emphasis added]
Michael Watts commented
I'm interested in the apparently full clause "who my dad punched was a hippie". I'm aware of this form, but in my mind it's not permitted in modern standard english; I would have to say "the man [or other noun] who my dad punched was a hippie".
And Eric P. Smith agreed:
I agree that “who” as a fused relative is not standard. Cambridge Grammar of the English Language (2002) is surprisingly categoric: “We cannot say, for example, *Who wrote this letter must have been mad.” (Page 1076). But I think it is growing, and I think it crossed the Atlantic eastwards. I first saw it about 3 years ago in a notice in Edinburgh University Library: “If we can't help you, we’ll put you in touch with who can.”
Iago clauses are definitely still Out There these days, though they're clearly informal and maybe to some extent regional. There are plenty of examples in COCA — for instance, this one from an NPR interview with Lee Tamahori:
The film stands or falls on this bear. This is a story that relied on a predator hunting down these guys and trying to pick 'em off one by one. You know, I didn't know who the actors were gonna be. I said it doesn't matter who the actors are gonna be . Who we cast is gonna do a great job. It's a good screenplay. But the bear, if it's done badly, can bring the whole film crashing down around their ears and making the actors look like turkeys.
From USA Today:
In the tournament, no one gets a choice. You play who you get.
From the New York Times:
Our commissioner has been supportive, saying,' Hire who you need, and we'll find the money later on.'
And of course the old expression "dance with who brung ya", or other cases where fused relatives with who are the objects of prepositions:
People have a right to be friends with who they want to now.