Military research works on using the tongue as interface for sonar or cameras.

The goal is to give soldiers super-human senses under water or at night.
Apparently the idea to use the tongue as transmitter for signals to the brain is already 30 years old.
Currently the so called Brain port features 144 microelectrodes that are taped to the tongue and transmit signals from input devices such as cameras or sonar sensors to the brain. There are actually successful tests already.

Everybody wants to get inside your brain. Sony for instance filed a patent for a brain interface last year. More details in this AP story on ABC News.

See also the military research on robotic animals.