Open University's Learning Space

The Open University in the UK is one of the leaders in online course development and is committed to developing open-source educational resources. They have made modules from their online courses (similar to OLI's) in a variety of subjects available for free through the Learning Space, and they have tried to make it easier for instructors to copy pieces of that material if they don't want to use all of it. They have skills-building modules as well as subject-oriented ones, which may be useful as a refresher for students in a more advanced course.