I like contrasty images. The few times I tried autolevel in GIMP gave pretty ugly results for me. But, using log histogram in curves, I almost always push the left bullet to the right until I touch the first non-zero value, and the right bullet to the left until idem. And I do this only for the VALUE histogram.
So, what I want to know if there is a tool or a plugin to do this automatically. I could make my own plugin in script-fu if there is not such a tool, but I don't know how to handle histogram values.