Keychain of mifare classic, one ultralight and more

Got these little treasures during the clean-up of the rolling loud hip-hop festival at ontario place. Probably were hundreds more, however I doubt anyone picked those up, much less kept them, after the concert (when they left).

Now to repurpose the blanks for something creative, amusing or what you might use 'em for.

Already have two of 'em (former laundry card, discarded gym membership) used to put my device on silent when at work and during the night.

Don't have the gadget to clone my FOB access tag, so that's out of the question. Cloning my current laundry tag just won't work (hash check fail, every time). Hahaha.