If you're a shutterbug, you could try selling your photographs. You might approach this by taking and loading lots of photos into stock photography sites such as iStock.com, stock.Adobe.com, Alamy.com, and shutterstock.com. Alternatively, you might offer your services photographing weddings and other events. Wedding photographers can earn several thousand dollars per gig -- but you'll need good skills, an impressive portfolio, and some happy clients to get to that point.

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.
While this isn’t exactly a long-term solution for making money (since you have to pay it back), it is a reliable way to get some extra cash when you’re in a pinch. It’s also a great way to make money by saving money if you use a personal loan to pay off high-interest debt, such as credit cards. Since getting a loan is one of the easiest ways to make extra money, we felt we had to include it.

While cryptocurrency is still relatively new, it will ultimately become the standard. Bitcoin and Etherium might be the primary cryptocurrency platforms today, but the US Dollar will eventually become the Digital Dollar by leveraging the blockchain. You can take advantage of the current boom in cryptocurrency by trading it through platforms like eToro and Kraken, amongst many others. 
For anyone who has capped at their current job, it could be time to look for another. If your salary is capped, it typically means that you are an expert for your current job, and the company can’t pay you anymore money for doing the same job. Take this as a sign to better utilize your skills at a more challenging, and subsequently higher paying job.