Originally it was glitter nail polish http://motherboard.vice.com/blog/itll-take-more-than-glitter-nail-polish-to-stop-snooping http://motherboard.vice.com/blog

Originally it was glitter nail polish http://motherboard.vice.com/blog/itll-take-more-than-glitter-nail-polish-to-stop-snooping http://motherboard.vice.com/blog/itll-take-more-than-glitter... ... the idea wasn't just to mark the screws to show if there'd been physical access, but to make a mark that's easily verified but very hard to reproduce, so you also know if your whole laptop has been replaced by the 'evil maid'. You need to photograph it to check! The actual bit in the 30c3 talk where this was discussed is here: https://www.youtube.com/watch?v=KV4XnvE2p34#t=54m24s https://www.youtube.com/watch?v=KV4XnvE2p34#t=54m24s