We're currently using it to generate static map images for a powerpoint export feature we introduced a little while ago. We initially were going to use Google's

We're currently using it to generate static map images for a powerpoint export feature we introduced a little while ago. We initially were going to use Google's static maps API but quickly ran into limits (only 5 custom markers, needing a different set of code to actually generate the maps) and decided to take screenshots of the map in our existing application. Besides actually being able to generate maps the way we want them, the other big advantage is that since it's sharing the same code base as our web product it's much easier to catch issues if they crop up. Being able to run headless on linux is amazing (on OS X you download the binary and it just works, getting 1.4 to run cleanly took a little bit of playing around to get Xvfb to play nice).