Assuming you've covered basics, these simple questions for your future colleagues and supervisors will help you get the info you need to evaluate the opportunity while helping you stand out as a attentive and engaged candidate. Showing that you are prudent about your next opportunity may also increase your perceived value to the interviewer by implying that standards must be achieved in order to acquire your contributions.
1. What has been your greatest challenge in the past 12 months?
Don't fool yourself. Every company has challenges. Every one. Better to understand a bit of it on the front end and be able to pick your poison. If it sounds too good to be true, it probably is - don't let a lack of transparency woo you into a blindside.
2. What do you expect will be your greatest challenge in the next 12 months?
Follow-up on the future evolution of the issues and what is expected to change as well as what is not.
3. What do you like most about working for the company?
Here's where you find out some of the reasons that people are putting up with number 1 up there. Look for things that are valuable to you, and don't underestimate the importance of working with very collegial, talented people. If someone says it's because they provide meals 3 times a day, be afraid. Be very afraid - unless you love living at your desk.
4. What are future career expectations for this role?
This is an issue that can sometimes get lost in the shuffle or glossed over. Get specifics as much as you can - how many years between the various promotions, what measures are in place for determing qualifications at future levels, and what directional options there might be as you continue to rise.
5. What is the company's financial history and projection?
With the sharp rise in layoffs and increased tendency toward contracts and project-based hiring, it's important to get into details like this. It's possible that not everyone you speak with will be qualified or authorized to answer this one.
There they are in all their simple glory. Ask 'em early and often, starting with screening and at each interview along the way. You'll hear multiple perspectives, get a consistency check, and be able to connect dots that you can't from getting answers from only one person. Take control of your interviews and get the data you need to wade through your choices!