Hi,
I think most of us were encouraged (forced?) to try learning a musical instrument as a kid, with mixed results...
for me it was the guitar, although that's now slipped out of the top 5 most popular...
Whatever the instrument was, we've all bee taught from a young age that playing a musical instrument is a good thing
Which is exactly why it's such a MASSIVE niche!
It's also a wide open niche, as most people haven't got a clue what to promote to make money in it!
Here's something that solves that all in one go, complete with a $150+ product to sell - http://alink.co/star
It takes 20-30 mins to go through the video training, and another 5-10 mins to get your payment buttons added
then there's another 5 minute video that shows you how to deliver the product with a couple of clicks
AND they show you exactly how to get traffic to your offer
*In case you were wondering, here's the Top 5 musical instruments for kids: Piano, Ukulele, Drums, Recorder, Violin
If you want to build an income taping in to all those frustrated, wanna be musicians here's your shortcut: | 
