<p>Physical tamper detection has been employed for over 7,000 years, but it is still a largely unsolved problem. We will review general problems with tamper-indicating seals and the many ways they can be easily defeated. A much better approach, called the anti- evidence method will then be explained. This will be followed by a demonstration of prototype anti-evidence seals, other types of novel seals, and real-time monitors. This talk is the result of work by the Vulnerability Assessment Team (VAT) at Argonne National Laboratory. The VAT is a multidisciplinary team of physicists, engineers, social scientists, and hackers who conduct vulnerability assessments and develop novel approaches to security. </p>