[lmm]

I use a Feitian epass for my personal accounts (it seems like yubikeys are USB or NFC whereas I wanted a single key that would do both). It fits on my keyring (smaller than my house key) and claims to be waterproof. I wish I could use something like that for banking - it's much more convenient than the little card readers some banks use, and frankly I have more faith in its security. A ring form factor would be nice, but I don't think NFC on PCs is ubiquitous enough yet.