A Japanese firm is working on a new technology that may make keys of any form, even keycards, obsolete. By using human contact as a key, it allows people who are verified to have access to an area to open a door simply by grabbing the knob as if it were unlocked.
Well, I mean, a keycard is still necessary, but you don't need to take it out of your pocket. That's because "as data travels through the user's clothing, handbag or shoes, anyone carrying a special card can unlock the door simply by touching the knob or standing on a particular spot without taking the card out." So while you'd need a card, you could just keep it tucked in your wallet at all times to allow you access to your home or office. A pretty cool idea if you ask me.