Opsec. New school is old school.

[vaskidmark]

http://www.wired.com/threatlevel/2013/12/better-data-security-nail-polish/

HAMBURG — If you’re traveling overseas, across borders or anywhere you’re afraid your laptop or other equipment might be tampered with or examined, you’ve got a new secret weapon to improve security. Glitter nail polish.

Don’t laugh. It works.

....

Some travelers affix tamper-proof seals over ports or chassis screws. But these seals can in fact be replicated or opened cleanly in minutes by anyone with even minimal training, Michaud and Lackey said. They instead advise borrowing a technique from astronomers called blink comparison. Here’s where the glitter comes in.

The idea is to create a seal that is impossible to copy. Glitter nail polish, once applied, has what effectively is a random pattern. Once painted over screws or onto stickers placed over ports, it is difficult to replicate once broken. However, reapplication of a similar-looking blob (or paint stripe, or crappy sticker) might be enough to fool the human eye. To be sure, the experts recommend taking a picture of the laptop with the seals applied before leaving it alone, taking another photo upon returning and using a software program to shift rapidly between the two images to compare them. Even very small differences – a screw that is in a very slightly different position, or glitter nail polish that has a very slightly different pattern of sparkle – will be evident. Astronomers use this technique to detect small changes in the night sky.

Glad to see that those tech-savy Germans are finally "discovering" this.  I remember this technique being used in the 1960s (first time I had reason to want to ensure no tampering.)  Go buy your own nail polish - your daughter will not understand nor will she believe it when you tell her the rest of the bottle is "still good".  Don't ask me how I know - the story is still painful.

stay safe.