MOOCs aren't just for current students. I think they can serve as professional development for faculty members as well. I don't have time for a MOOC during the school year, but I am committing to doing one this summer.
I think that instructors can approach MOOCs in two ways: 1) professional development, and 2) a search for improved pedagogy.
As professional development, learn a new statistical skill or freshen up a dormant one. Learn R. Learn Python. Freshen up on your non-parametric skillz. Take a course on data mining or using statistics in order to gain business insights.
Unofficial documentation of your course progress is typically offered just by taking the course. Official documentation/grade reports are usually available for a reasonable fee (my husband has taken a few such philosophy courses and paid around $50 for the official documentation).
Another way to use these courses: Don't take them to learn new skills, take them to learn new ways to teach your old content. Steal a good discussion board prompt. Find a new text book. Discover a useful interactive website that explains effect size or confidence intervals.
Some universities advertise their own MOOC lists, and I welcome you to Google around and find different classes. Here are the data science/statistics courses for two of the big MOOC organizations, Coursera and EdX.