Coursera is a platform that has 12 million participants from 190 countries taking over 1000 online courses from 117 institutions around the world, including several prestigious Universities such as Stanford, Yale, Princeton and the University of Edinburgh (as at March 2015). Courses are free. These are called Massive Open Online Courses (MOOCs). Most provide a certificate but you are not obliged to do the graded quizzes and assignments to earn a certificate. You are welcome to just watch the videos (audit the course). Courses cover a very wide range of topics from Public Speaking to Quantum Physics. Some courses are self-paced but most of them run to a timetable with weekly lectures and quizzes. Some run in parallel with the equivalent on-campus course. Courses vary from 4 to 10 weeks long and the weekly commitment can vary from 3 to 15 hours per week (if you do the quizzes and assignments). You need to create a personal account to access courses.
http://www.coursera.org
edx is a platform that provides over 300 online courses from over 60 academic institutions including several prestigious Universities such as UC Berkeley, Massachusetts Institute of Technology, Harvard and Stanford. Courses are free. Most provide a certificate but you are not obliged to do the graded quizzes and assignments to earn a certificate. You are welcome to just watch the videos (audit the course). Courses cover a very wide range of topics from The Ancient Greek Hero to Principles of Written English to Combinatorial Mathematics. Courses run to a timetable with weekly lectures and quizzes. Courses vary from 4 to 10 weeks long and the weekly commitment can vary from 3 to 15 hours per week (if you do the quizzes and assignments). You need to create a personal account to access courses.
http://www.edx.org/
U3A UK provides a list of several UK resources
http://www.u3a.org.uk/useful-weblinks/92-educational-web-links.html
TED is a nonprofit devoted to spreading ideas, usually in the form of short, powerful talks (18 minutes or less). TED began in 1984 as a conference where Technology, Entertainment and Design converged, and today covers almost all topics — from science to business to global issues — in more than 100 languages. Meanwhile, independently run TEDx events help share ideas in communities around the world.
http://www.ted.com/
The Royal Society of New Zealand runs public lectures Many can be viewed on their website at:
http://www.royalsociety.org.nz/events/viewing-room/
Or they can be viewed in high quality on their vimeo site at:
http://vimeo.com/channels/royalsocietynz
U3A Online is an Australian-based virtual U3A that makes courses available to U3A groups and to individuals. The courses have been developed by Griffiths University. Individuals can join for A$25 pa for any number of courses or U3A groups can join for A$15 pa plus A$20 for each course run each year. The courses are delivered by course notes that are downloaded.
http://u3aonline.org.au/