Mark Your Territory sounds at first like a really silly concept, but the critic will quickly discover the depth of thought that went into Andrew Quitmeyer's invention.
Essentially, you begin with a set of "enhanced business cards" marked with your name and a QR code, coated in silver. With a spike on one side of the paper it can be wedged into the dirt or else stuck to a wall with the help of an adhesive backing.
You are instructed to connect the marker to your smartphone before you proceed to pee on it. The detector confirms your identity and through a special MYT app it authenticates your position and checks you into Foursquare. Mark Your Territory merges the physical and virtual words. Check it out and you'll uncover even more unexpected features.