Personally, I have no issue with other people using my coffee mug. It increases the chance of me picking up a wicked case of cooties and girls love cooties. Seems Israeli designer Efrat Gommeh has other plans. His Lock Cup is a basic coffee mug with a hole in it. A plug for the hole with a keyring is included so you can carry around the plug on you. This ensures that the only person drinking liquids out of that damn cup is going to be the owner, period. It’s a novel concept and would most likely sell like wildfire if released commercially. Now if only we could apply the same idea to the toilet…