Know yourself
Anything you wrote in your application form, cover letter or CV is fair game for an interview question, so look back over your copy of it and be prepared to expand on everything in it. The interviewer will probably have your CV in front of him / her and will just have reviewed it. Therefore, make sure your CV is fresh in your mind too!
Are there aspects of your professional or academic background that might raise a question in the mind of the interviewer? Be prepared. Review your CV, cover letter and / or application from the perspective of the employer and the job you've applied for. Apart from the content of your CV, what else do you want the interviewer to know about you?