Interestingly enough, when I needed fonts/sprites again in a couple of years, I resorted to a set of multi-layer GIMP files with a set of rulers and grids which

Interestingly enough, when I needed fonts/sprites again in a couple of years, I resorted to a set of multi-layer GIMP files with a set of rulers and grids which I would export into the X bitmap format (which is a text format consisting of a bunch of C constants). (I didn't need to dynamically generate text on that project, just fixed pre-prepared strings.)