I have sometimes asked the hiring manager to describe when and why he gave a report a negative review about something. This usually causes a long pause.

It isn't at the end, but a few times I've asked mid-interview for one of the team members to give me feedback as though it were for a peer review.

I've been known to ask what an interviewer's favorite NPR show is. It's great if the interview is at a location I'd have to relocate to and they answer with a show carried locally I've never heard. That's how I learned about "Says You" (which is the correct answer to my question, with points for effort if it's "Wait, Wait Don't Tell Me" or "Prairie Home Companion").