Fab
Excellent proof of concept.
There are pros and cons in using this sort of thing in real life, but I can see how it could augment existing security protocols on plastic cards and would certainly be useful for portable identity verification where the verifier isn't able to carry around a device with a screen on it.
For credit cards I see its application being more in America where photos on cards are the routine versus the UK's reliance on PINs.
Might not work for those of us who prefer our hair to have a different colour for each day of the week though!
Still, it's cool tech. I'm sure it'll find a use somewhere.