For the wordprocessor project, here are some points about writing such
beast.

I think writing the word processor in C or C++ is out of the game. Why
not use Tcl/Tk?. Tk is an easy and tested X toolkit and it can be
extended in order to handle the special cases in the program.

Tk's text widget. We can have text with different fonts/colors at
the same time. As far as I know the next version of Tk (under
contruction) will have more support for interspace between lines and
things like that).

The problem with TeX is that every time you want to see a preview of a
page, or print something you have to go throug a lot of programs (tex,
dvi2ps, ghostscript?) and this makes the process slow. 

As far as I know, it is easier to generate groff output. We could save
the file in a propietary format and the user may choose the output
subsystem (groff, TeX).

--
Miguel de Icaza.