What questions should I ask staff/students on applicant/open days?

For example:

What is the nightlife like?
Is the cost of living here cheap?
What optional modules do you offer?
What is the best/worst halls? Are there any underrated halls?
When will I hear back from you, after today?
What are the sports facilities like?
Do you offer any help or guidance for things such as temporary jobs?

For those already at Uni, what were some questions you wish you asked when you were going to the open days?

For example:

What is the nightlife like?
Is the cost of living here cheap? I would ask people for specific figures if cost is an issue for you. People have vastly differing ideas of "cheap" and "expensive". You could also ask if any bursaries are available to students.
What optional modules do you offer? With optional modules, it's worth asking how long particular modules have been offered for, and if there are any plans to change optional modules. Some unis will change their optional modules when new staff leave/arrive and this may help avoid disappointment.
What is the best/worst halls? Are there any underrated halls?
When will I hear back from you, after today? I wouldn't ask this unless you're at an interview, and maybe not even then. This won't make them respond any faster, and it's unlikely you'll be able to get an answer, and it just seems really demanding. It's fine to ask a more general question about when you'll next hear from them if you accept an offer etc.
What are the sports facilities like? You could also ask about sports societies if this is something you're interested in.
Do you offer any help or guidance for things such as temporary jobs?

For those already at Uni, what were some questions you wish you asked when you were going to the open days?