Heh, this got me thinking of the feasibility of cryptographically signed, err.. signs.<p>A QR code can hold 2953 bytes of binary information, so more than enough for a 2048 bit public key.<p>Same code can also hold 4296 bytes alphanumeric, which would be sufficient for even a decently long message and its associated signature.<p>A government could post the fingerprint of their key on a site, and post a QR codes containing a signed message about the sign on the sign itself.<p>Like so: <a href="https:&#x2F;&#x2F;imgur.com&#x2F;a&#x2F;fWZpt" rel="nofollow">https:&#x2F;&#x2F;imgur.com&#x2F;a&#x2F;fWZpt</a><p>Sign sign sign. Got some semantic saturation happening now.<p>Sounds somewhat absurd, but definitely feasible for homeland-security-type things like this random box.