Remember that every interview is different, and there are a million jobs out there. Some of these suggestions will have to be tailored to you specific situation. Here are a few questions that may be appropriate to ask:

Is there an opportunity for promotional advancement within the company?
A question like this indicates that you are motivated and thinking about your long term future. It also states that you are viewing the position as a career rather than just a job. Employers like motivated people who want to advance through their contributions to the company.

Is the company in an expansion mode, or are their any new developments in progress?
This question indicates your level of interest in the company. You are interested in knowing about the growth and forecasting of the company which makes an employer assume you are interested in a long term position.

I am always interested in educating myself. What type of professional development programs are available?
If you show that you're interested in ways to develop professionally, employers will view not only your current skill set, but they will also consider your potential skill because you have shown that you continually grow in this area. In addition, many companies offer professional development programs that are under utilized. Often HR managers have to justify their budgets, and recruiting people interested in utilizing the program helps the HR manager with their argument.

Last year the industry saw a small decline (gain). How has this impacted the company?
Showing that you are up-to-date on industry news increases your chances of getting the job. It shows that you have an active interest, and also that you have the ability to extract data and apply it to appropriate situations.

When do I start?
This question should never be asked during the interview - Not even jokingly. Usually it never has to be asked period. If you do have to ask it - save it until after you have been offered the job.