Adtec AD-HSM10 is the world’s smallest Bluetooth headset for mobile phone. It measures 0.9 x 0.86 x 1.2 inches and weighs only.01 ounces or 5 grams. This smallest Bluetooth is from Japan, not sure if they are going to ship it out or not. If yes, it’s going to cost you around $78.

[via Slashphone]