Time In Words is a little piece of software I created just as an
exercise in C.  I saw this screenshot of some guy's screen saver in
KDE 4.2 which had a clock that said something like "Ten to five", and
I decided I'd make something similar.

What I made was both a program and a library (header) file of
functions.  The program outputs the current time in words, but not on
the "Ten to five" format, but on the "four fifty" format.
Furthermore, the output is 24-hour based.  If I feel inclined enough I
might extend the library with a method that provides the time in the
"Ten to five" format, however it should be noted that this format
isn't exactly standardized as far as I know, and therefore in the
event of the extension of the library, the format will be of my own
preferences.

You are of course welcome to alter the format to your own preferences
as this is all free software (see COPYING).