This is an amazingly good idea!

Schneier on Security: Fingerprinting Paper The fingerprint of paper Paper’s Natural ‘Fingerprint’ Could Be Built-In Passport Protection

Any piece of paper becomes a secure token. While - as with any problem in security - you have to be careful about what you claim the token “proves”. Still the applications are pretty interesting.

You could have a warehouse full of unlabeled(!) boxes, with only pre-printed guide marks to indicate where to scan.

You could issue temporary ID cards just by scanning a pre-printed bit of paper - you do not have to print anything on the paper. In many ways this is more secure, as if someone picks up a lost ID card, there is no way to determine anything - company, user, privileges, or expiration - without access to the (presumably secure) security database. Manufacturing fake ID’s becomes impossible.