Just did a bit more searching and found this site that seems to have a product, though I'm not sure if it is actively in production and available. Source: over 2 years ago

Jewelry (ring, necklace, bracelet, earring) seems perfect for physical authentication devices: it's easy to carry, always available, and hard to lose. In the middle ages nobles used signet rings to stamp official documents with their unique personal pattern. In modern times, you can stash a Yubikey in a bulky wristband or put it on a necklace chain, but these are not very stylish. There are a variety of "smart... Source: about 3 years ago

If you haven't heard of him, the joke's on you. Maybe. In any case, his work is worth looking into. He has done interesting work in font creation, font building primitives, rasterization, 2D drawing, and resistant social network graphs (which turns out to be more or less equivalent to the Old Sk00l Google Juice system). He was recently instrumental in performing a wonderful experiment in editor building --... - Source: Hacker News / about 1 year ago