It would be handy to be able to adjust the amount of spacing a line gets in the lister file display. Currently, spacing is determined by the font, but some fonts have too much spacing by default.
A good example would be the new Windows Vista font Meryo font. It's the new Japanese font (but other western fonts have the same problem) and is a lot better than the old one, but there is too much spacing for use in a lister between lines.