The Doorcap Smart lock from Hyundai lets you lock your door and throw away the key. However, you'll need one of the six provided RFID passcards to let yourself in.
But wait, there's a hidden number pad to enter your PIN code if you don't happen to have that passcard on you. The Doorcap Smart also functions as an alarm if somebody breaks in, and it re-locks itself if you unlock it and then for some reason don't open the door.
We're thinking that the keypad/PIN would be enough, but maybe the RFID card adds an extra layer of security. So perhaps there is a good use for this RFID stuff after all. Doorcap Smart is available now for $249.