Any sufficiently advanced technology is indistinguishable from magic.--Sir Arthur C. Clarke
Case in point, my flat's "entry system" or, um, lock. As you can see, it's keyless, at least in the traditional sense. You can apparently activate it by keypad code, or telephone code, or by using what seems to be a watch battery glued to a stick.
While I'm at it, let me include another of my favorite Clarke quotes:
The greatest tragedy in mankind's entire history may be the hijacking of morality by religion.