CreativeLive is a unique online learning service in which the courses are taking place live with both studio audience and online viewers. The online audience can interact with the instructor and ask questions live via chat. The chat feature also allows you to interact with other viewers (either about the topic being learnt or in an off-topic chat room).
CreativeLive started as mostly photography centered with a single course over the weekend, and slowly grew and now offers many courses in a variety of subjects such as photo editing, design, music and self improvement.
The courses are free to watch when they are live and they are also re-broadcasted after the course is finished (of course no live questions via the chat during re-broadcast)
You can buy a course which gets you access to the course's video at any time and the course material (many courses have PDFs with summary and additional information)
Courses lengths vary and can be a single day, few days and even a month. Sometimes they hold a Photo-week or Photoshop-week during that week CreativeLive gathers an impressive collection of lecturers, many top of their field, each giving a short course in their area of expertise.
Course's price is dependent on its length, and are reasonable (there is usually a reduced price if you buy it before the course ends)
Not much to dislike about CreativeLive, it sometimes can be difficult to get your question answered on popular courses, but the moderators do their best and try to get the frequently asked questions answered (in some cases another viewer may answer your question in chat)
Courses hours are daytime in the west coast of USA which may not be optimal for viewers in other countries.
Many courses to choose from, for all levels, try one of the live courses (free) and see if they style of teaching works for you.
Some courses are really in depth, and even if you think you are familiar with the course subject you end up learning new things.
I've been following photography their courses for few years now and I feel it got me a better photographer.
The ability to ask questions during the course is a unique selling point for me, which is usually only possible in 'offline' courses.