They include products and devices such as Bluetooth headsets used with cell phones, handheld metal detectors used by airport security, iPods, iPhones, electric blankets and pills that are swallowed and used to image internal organs by transmitting wireless data.

CNN: Study: Headphones could interfere with pacemakers

With 802.11a, the wireless technology currently favored by Sony (nyse: SNE - news - people ) for transmitting video and music on wireless home networks, the signal spectrum used is in the 5 gigahertz range.

FORBES: Magazine Article

Outside of the cellular telephony world, this seemingly simple occurrence doesn't really happen -- typical wireless signals have to take turns when it comes to listening and transmitting.

ENGADGET: 'Stanford gurus enable two-way radio communications. Over.'