'Experimental media artist Daito Manabe choreographs a synchronized face dance for four friends by hooking them up to the Face Visualizer, a device which converts music into electrical impulses that stimulate the facial muscles.'
The video above is funny to watch. Each of the guys' faces has its own life - uncontrolled by them. Manabe states of his motivations for this project:
'I got inspired “we can make fake smile with sending electric stimulation signals from computer to face, but NO ONE can make real smile without humans emotion”. This is words from Mr. Teruoka who is my collaborator to make devices.' 
Another project that uses the face as an interface, or a blank canvas, is Emotor (AEM, p 160, see linked entry). Artist Tim Hawkinson stated the following about his project:
'I started thinking about imagery and the face and how any kind of input into the face - no matter how irrational or unpatterned - would still create something we can decipher, look at and read and get some message from... Emotor uses the expressions of the face that are so cued into reading the face. I took a picture of myself and cut the features up into little peaces, like a puzzle, and rearranged the features. And each time I did it, I created a different emotion, and that's just something I read into it.' 
So both artists used technology to let their faces display emotion. It sounds a little backwards. The only thing that computers can not feel are emotions. It is probably one of the biggest distinction between man and computer. The artist both seem to explore human emotion and how this is displayed on the face. The data typical characteristics for the emotions are digitalized and reproduced. N. Katherine Hayles states about this informatization of the self (virtual body):
'... the body is neither simply material object nor informational pattern but both at once. The crossings and interpenetrations constituting the virtual body call for a more sophisticated and nuanced approach than simply binary thinking can provide. It is when one duality is chosen over another - when the body is seen as information - that its erasure seems possible' 
I don't think that Emotor or Face Visualizer cross that line. Although Manabe gives bodyhack workshops which suggest a close relation between body (wetwear) and hardware. But don't worry; as seen in the video, a smile is a smile and no computer can simulate a real one - at least not yet!
 Tim Hawkinson, in Art and Electronic Media, p.160
 N. Katherine Hayles, in Art and Electronic Media, p. 262