Build poor-man's spritesheets using bash, Image Magick, and pngcrush.
I use this with my goatee
tool when building web pages. It's a little
too specialized for general consumption.
usage: mkatlas -o outfile [options] image [image2 ...] > metadata.src.css
-n val set the namespace (prefix) for all variables
-r val set the relative path to the image in the CSS
-f #rrggbb flatten the output with the specified background
Image names can be BR
which means to move down to the next "row"
(clearing all previously added images):
mkatlas -o atlas.png img1.png img2.png BR img3.png img4.png
Bash, Image Magick, and pngcrush.