As a word nerd, I particularly dig the etymology, but the W'pedia entry gives a more thorough description and several other examples.PRONUNCIATION:(SKYOO-uh-morf)
MEANING:noun: A design feature copied from a similar artifact in another material, even when not functionally necessary. For example, the click sound of a shutter in an analog camera that is now reproduced in a digital camera by playing a sound clip.
ETYMOLOGY:From Greek skeuos (vessel, implement) + -morph (form).
NOTES:A skeuomorph can be employed for various purposes. Since people are used to the click sound of a camera as feedback that the picture has been taken, it is now artificially-produced in digital cameras. Other examples are copper cladding on a zinc penny (for familiarity) and wood finish on a plastic product (for a more expensive look).
I enjoy the tension between utility and familiarity. Sometimes the skeuomorph is superfluous, merely decorative -- a designerly harkening back to the design that informed it. Other times, there's a usability component -- the copper coat on a zinc penny, while not technically necessary, would seem to prevent a lot of errors. And I know some users who find it helpful to hear their digital camera "click".
And I am SO going to incorporate a skeuomorphs-hunt activity in my New Media Studies classes! If you think of any, please comment.