I use Moodle in a professional context : I am co-leader of SILECS, a small free software IT service company based in Grenoble, France. Our customers are mainly french universities. We propose to them Moodle installation, customization and support.
For the documentation effort, I try to participate in the french documentation, by updating obsolete translations and beginning new ones.
I also try to contribute to english documentation, mainly by completing existing pages, sharing my experiences. My philosophy is "write the doc you'd like to have found".