fonter is a console font editor. It's pretty nifty, and several console
fonts in cLIeNUX core are from the fonter source distribution, or were
created with fonter. fonter needs

TERM=linux  

and should be run with the current font being 16 lines high. ( or more?) 
Otherwise the program itself is fairly self-explanatory as far as when
you're in it. The cLIeNUX version uses the current directory to load/store
fonts. When fonter runs it uses the font it's editing as the current font. 

It does have a few commandline switches, I notice in the source, including 

-h for help.

These are the authors docs...

Please note that the F1 command to save in pcf format is
not really setup correctly right now.  Now, it saves a vga.pcf
file, with the name vga inside.  You can change the filename,
or edit the file with a good editor, such as vi or vim, and
change the identifier.  That way, you could use it in X,
without overwriting your current vga.pcf.  Please note that
the identifier inside vga.pcf will only support 3 characters.
Here are a list of few bugs, which may not be my programs fault:

o  I've had a report of the whole screen flickering when you toggle a fonts
   pixel on or off.  This is probally a problem of your video card not liking
   the ioctl font controlling codes.  Does it flicker when you type setfont?

o  If you list the files, and there is a font over 14 chars, the program will
   crash. [ BSOD in Linux. wierd. BttyOD actually ]