Free (zip file) - Number symbols to go ontop of images (to make stacked items)
This Gimp file (can be used with other programs too) has 10 layers.
Place an image in the base layer, and turn on/off layers as desired to get a little number from 1 to 9 at the top left of your image.
Size of number is 20x20, but can easily be changed.
Good for games where you need to stack items and keep count.