Teaching and tutoring English as a second language is a great way to make money online, not to mention open some doors for you to travel the world if you'd like. While full ESL (English as a Second Language) accreditation is recommended, as long as you’re a native speaker and have the ability to teach, there are people in countries such as Hong Kong or the UAE who are willing to pay upwards of $25/hr for you to tutor them English via Skype. Check out Indeed, Learn4Good and Remote.co for remote english tutoring jobs or sign up on a specialized site like VerbalPlanet or Chegg Tutors.
21. Facebook – Facebook swap shops are great for selling things locally. It’s like CraigsList, but a little easier. You simply search for swap shops in your area and ask to join the group. Once you’re in, take a picture of the item, write a quick description with the price and post it. It doesn’t get much easier than that. You can generally expect to get about what you would get at a yard sale, maybe a little more.
Not only that, you will be able to evaluate business ideas much more intelligently once you've gone through this whole process. You will understand the fundamentals of keyword research & analysis, traffic & lead generation, social & affiliate marketing, monetization & conversion testing, and traffic analysis. These skills will help you immensely in ANY business you ever decide to start (online or not, passive or not).
Set up a roadside stand. Depending on where you live, you could profit handsomely by setting up a roadside stand. If you live near a resort area, for example, you could buy cases of bottled water, put them on ice, and sell them to passers by for twice what you paid. Selling fruit and produce you grow yourself is also a smart idea in highly-traveled areas.
One of the cool things about Google AdSense is that it's so easy to get set up. If you have a blog or website, you can sign up for a free Google AdSense Account. From there, Google will give you a unique code that you will paste onto your website. Google takes it from there, tracking your page views, traffic, and earnings on your behalf. There is no upkeep or maintenance to get this thing going, which makes it a no-brainer if you have a website already.