I came across this today and though some of you may be interested. I've never taken a course off this site and really know nothing about it. However, it claims to be free and may be informative. Sign up at your own risk
I posted that recently too, but I'll chime in. I have not taken this class but my daughter is taking Genetics right now and we're impressed, and have plans to sign up for something else soon (and I might take Equine Nutrition just for fun).
The Genetics class my dd is taking has nearly 20,000 people enrolled from around the world. Obviously people take it for different reasons, and only those who finish all the requirements get anything on paper (which may not be worth anything...) but it is a neat program.
All their courses are free. Coursera has been profiled recently on PBS and NBC so they are totally legitimate.
I'm also taking the Genetics and Evolution class they are offering right now--it's my first class through them and I'm really enjoying it so far (I'm also enrolled in the equine nutrition course).
For some of their classes they are offering a new thing that confirms that it is really you who took the class (helpful when filling out applications for schools, jobs, etc.). It's not offered for all of the courses right now and of course costs money. The actual courses are free though and many still offer a certificate if you complete them.
They're working on getting some of their classes approved for actual college credit:
"Here are 2 articles discussing the ACE credit review process: