They typically explain what I will be doing fairly well (domain, technology...) so I tend to have this quite clear after the first part of the interview.
I like to ask:
"What is the timetable?"
If they do regular unpaid overtime they are usually not very aware of how much of a red sign this is for me, and for some reason they will almost boast in, like "Uh, you know when you come in but not when you come out". As a bonus, I get to know if they reduce the working time in summer, and whether they have a flexible timetable (in the good sense).
If I haven't been shown the workplace (their mistake), I ask where I will work, is it a big/small office, where it is located, etc.
I also like to ask: "Do you do unit testing?".
Also, "Do you do code reviews?".
At some place I asked whether they had a source control system. They didn't.