And two points to keep in mind with this:
1 - You don't have to put other people down to do this. It does not have to be "Why those other guys suck."
2 - It does not have to be a big difference. It could be something unique about your past experience. It could be a slightly different perspective you have. If you are a musician, it could be an aspect of your pre-show routine. If you are a business person, it could be what you like to read in your spare time. It all helps people get to know you a little better.