Researchers from U.S. Universities and in collaboration with medical institutes have recently designed and tested a somewhat "unconventional" (and maybe revolutionary) human-computer interface using the tongue.
In detail, their aim is to allow people with mobility disabilities to control their wheelchair by using a tongue implants (piercing). The developed system is called TDS, standing for, Tongue Driving System.
See the following video:
The full research article can be found here: