DEF CON Talk on Bypassing Tamper-Evident Devices

HN points to it in threads about physical security and tamper-evident seals as an informative look at how easily they are bypassed.

A DEF CON 19 talk by datagram introducing tamper-evident devices. It reviews how seals and similar products are designed and shows that they are often easily defeated, drawing on the DEF CON tamper-evident contest.