Furcodes are awesome. The not only have a QR scan thingy, but a website on the other side that you can put into any computer and automatically see the animals website. It holds info like allergies, medicine, medical problems, vets, facebook, email, etc.
I got mine on ebay for $1.36! If you buy them direct from the site they are $19.99
So check out ebay first.
But their website is
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