I've made a basic grid image editing tool suitable for drawing icons for toolbars, buttons, whatever other little images may be needed. Its very basic; color selection,
load / save to .png format, a re-sizable grid (for now, up to 64x64). It can draw lines, filled boxes, or outlined boxes.
The innards use my smg2 gui toolkit, and my sml2 standard library. The only thing I didnt write myself is the .png loader / saver. Not much to it, but it allows me to whip up a simple image on-demand.