When we hacked the Trezor back in 2018 at CCC, I argued that these holographic stickers were worthless. They are easy to remove with hot air.

However, I was wrong. I have found the perfect application. When used on a cassette tape, the sticker removes the ferric oxide bonding from the plastic of the tape! It is actually tamper evident!

This is by far, the best tamper evidence I've seen. The picture shows the clear (damaged) portion of the tape under the playback head.

The tape still plays, just the audio drops out momentarily.

So yeah, tamper stickers on cassettes. They work.