There is the great NFC LockScreenOff Enabler to easily unlock your phone. But it does only make sense to me when I wear the corresponding tag on me.
Balancing my phone in the left hand makes it easy to unlock, when you wear a ring on that hand (same for the right hand of coures). While waiting for my ring from the Kickstarter campagne I made my own:
- Take apart a NFC keyfob, remove the coil and unsolder the chip.
- Find a tube and add layers of tape to match your ring size, use grease underneath the tape for easy removal of the tube lateron (I broke my first ring removing the tube)
- add a layer of glass or carbon fabric for reinforcement
- wind the wire around the assembly, glue the chip on top of it and resolder
- use plastic around as a cast and fill with polyester or better epoxy
- cut, grind, remove tube and tape and polish!
Watch the short video ("Unlocking w NFC" youtube link): the ring works really smoothly with my i9505.