If you've ever had an interest in learning about Buddhism, now is the perfect opportunity. You can take a Harvard University course on the beliefs, practices and scriptures of Buddhism online for free.

"I'm not just a nerd," proclaims a bespectacled 13-year-old named Thea, speaking into a microphone on stage. "I'm also a geek." The audience laughs.

Crossfit's intense workouts are a polarising subject of discussion. It seems the first rule of Crossfit club is that you must never shut up about Crossfit club, and on the flip side, the sport (routine? Discipline? Hobby?) has its share of haters. So let's take a minute to cut through that for anyone who's intrigued but isn't sure what they would be getting into and whether it's worthwhile.

MOOCs, or massive open online courses, can be very useful and a lot of fun. But why do them alone? Turn your next online course into a book club-style exercise.

If you've been itching to learn photography but aren't sure where to start, former Stanford professor and Google teacher Marc Levoy has released his entire course, which includes video lectures and slides online for free.

You can never learn enough when you're practising design. The Summer of Design 12-week email course from designer David Kadavy, based on his book Design for Hackers, is currently free if you sign up in the next 12 days.

If you're interested in making music, learning the basics of music production and music theory will serve you well -- and this free course from NYU will teach you the ropes, at home, using your own computer and music you already know and love.