The best online learning experience I had was a MOOC (Massive Open Online Course) called Learning to Teach Online, run by Drs Simon McIntyre and Negan Mirriahi from University of New South Wales, Australia.
It was great because it allowed for complete techno-newbies to participate and succeed; there were strong efforts to engage the thousands of students taking it, through a combination of mediated forums and the summary of common questions via a start-of-theme video; it used a combination of peer assessors to mark the work of those who sought the certificated badge; the videos used for instructional purposes came from a range of disciplinary backgrounds and were rarely more than 8 minutes long.
They’ve run it again at least twice since I did it, and won awards for online teaching based on this MOOC. I warmly recommend it.