I’ve not found any yet, and to be honest it’s not a hobby I’m looking to get into – but even if you don’t have a smart phone you can take a photo and scan that at a later date. I can’t find one at the moment, but there may even be a site you can upload a photo to and have it scanned by the site.
QR Codes are fascinating, invented by Toyota for tracking stock – there’s an excellent wikipedia articles about them;
