Equidistant Conic Graticule Generator Script
I've written a little Ruby program to generate a graticule for the equidistant conic projection. This projection works reasonably well (For fantasy map making purposes) for medium scale maps, particularly in middle latitudes. Countries to mid sized continents.
It requires Ruby 1.9 to run and includes instructions in comments at the top of the file. It has a command line interface and produces SVG output you can use in Inkscape or other vector graphics editors.
A good rule of thumb is to pick standard parallels 1/6 of the way in from the top and bottom of your map.