Coursera. UPDATE: we're doing a live, updated MOOC of this course at stanford-online July-2014 (not this Coursera version).
See here: CS101 teaches the essential ideas of Computer Science for a zero-prior-experience audience. Computers can appear very complicated, but in reality, computers work within just a few, simple patterns. Iversity. FutureLearn. Learning. Open Learning Initiative. MIT Open Courseware. OpenLearn. Saylor Academy. OPEN2STUDY. Udacity. Khan Academy. Academic Earth.