This is a very difficult question for someone to answer in the abstract, because special questions are ones related to your personal needs, tastes, and interests. You will want to use this opportunity to get a sense of fit. For example, if you are religious, you might want to know about the religious life on campus including places of worship and clubs. If you are highly social, you might want to know in detail about how hard it is to get in the fraternity or sorority of your choice and what Greek life is like on campus. You might also want to find out about whether there are places you can study on campus if you are a commuter student or what sort of late night hangouts there are if you are a night owl. The main thing you want to do is ask yourself what will affect your daily life that is not discussed on the campus website but which matters to you personally.