Final answer:
Infrared technology allows two devices to temporarily communicate over short distances, with only one of them needing to be powered.
Step-by-step explanation:
The technology that is designed for only two devices to temporarily communicate over short distances and only one of them even needs to be powered is Infrared.
Infrared radiation is commonly used in TV remotes to transmit signals by modulating an infrared beam. This technology requires direct line of sight between the infrared emitter and detector. However, some remotes now use Bluetooth instead of infrared to overcome this limitation. Bluetooth is another wireless technology that allows communication between nearby devices, but it is not specifically designed for only two devices and does not require one of the devices to be powered.
Therefore, the correct answer to the question is Infrared.