If you are good at Mobile app development, or perhaps you are an experienced welder, you can create educational videos and articles, and even teach a whole class by signing up to websites that offer such services. Making an online course is no easy task, however quality content and a little effort can make your course several hundred dollars worth, so it might be a good idea to consider.
The plugin works with all major payment gateways including PayPal, Authorize.net, and Stripe. You can even offer site visitors coupons or free trials. You can also establish any kind of membership system you want from dripped content to freemium to a full pay-to-access everything setup. It also includes a setup wizard, the ability to opt out of features, and more.
The second big takeaway for me, was to pick a niche you know, you find interesting AND where there is demand for your product – ie willingness to buy/pay.  A lot of people only remember the first part of this 2-part formula, and end up creating a blog on knitwear for kittens.  But it’s the overlap of passion and profit that Ferriss stressed so much.