I wrote a little tool that decodes the data optically from a credit card, using a photo of the credit card and an iron solution. https://www.anfractuosity.com/

I wrote a little tool that decodes the data optically from a credit card, using a photo of the credit card and an iron solution. https://www.anfractuosity.com/projects/optical-magnetic-stripe-reading/ https://www.anfractuosity.com/projects/optical-magnetic-stri... I'm planning on seeing if I can decode data from higher density mediums with the same approach, when I can get my hands on some iron nanoparticles.