Here's a list of words that as of 2012 ought to be officially retired as no longer recognizable by those under 25.
Please add yours to this starter kit....
* Dial (noun and verb)
* Dial tone
* Busy signal
* Hang up
* Film (verb and noun)
* Tape (verb and nonsticky noun)
* Erase? (taken over by "delete"?)
(List courtesy of Jeff Jarvis on Google+)