Knot again: Just how headphone cords manage to tangle themselves up without any outside interference is one of life's minor mysteries. Bluetooth-enabled devices, however, offer a solution to this problem.

Sony has contributed its new DR-BT100CXP headphones to the cordless cause. These are basically upmarket earbuds that are joined to a small Bluetooth receiver, which also serves as a remote control, allowing the user to change tracks and adjust the volume. The earbuds connect to the receiver with 60-cm cords, so you don't entirely escape the tangle, but these are the only wires.

The device also includes a microphone so that you can use them as a cell-phone headset. Moreover, while the earbuds do not deliver as high quality a sound as regular mid-price headphones, they are at least a step up acoustically from the noxious creations that come packaged with your DAP or phone.