If you live near a university, there are likely all sorts of research studies looking for participants. While I was an undergrad at Virginia Tech, I got paid $500 to participate in a 6-week dietary study. The study provided all my meals and paid me, but I had to eat a 5,000 calorie diet of 50% fat for 6 weeks, plus I had multiple muscle biopsies, urine/blood testing, etc.

Ever since the idea of online auctions came into existence, the online selling market has been on the rise. Many are interested, but don’t know how to get started. There are still all kinds of ways to make money by selling online, whether you’re selling what you already have or buying and selling like a store. Before we get started, here are a few general tips when selling anything online:
If you're running on fumes, financially speaking, but you have some money coming your way soon, consider pawning something of value to borrow fast cash. Of course, to get those items back you'll need to pay back the loan with interest. If you don't pay it back in time, that you'll lose the item. If it's really something that has a lot of intrinsic value to you, don't do it. But if it's something that doesn't, you can certainly consider it depending on your situation.

Market your course: The beauty of using a course to make money online is that you can continue to sell it for as long as you’d like. Look for niche communities on Facebook, LinkedIn, or Reddit that might benefit from your content. Guest post on relevant blogs and sites. Look for anywhere you might be able to get in front of the right people. With just a few hours a month you can continue to generate sales.
What, specifically, can you sell on Fiverr? Anything from graphics and design services, to digital marketing, writing and translation services, video and animation services, music and audio, programming and application development, business services and lifestyle services that includes anything from celebrity impressions, to gaming and even astrology readings. 
Amazon Mechanical Turk is a service that lets you make money online through doing paid microtasks. Each task is something simple that requires human interaction like rating search results, checking for the right spelling on search terms, categorizing the tone of an article, or even basic translating. You can do these tasks from anywhere you want and make money online from the world’s largest e-retailer.

Watch other people’s kids along with your own. There’s a good chance your friends who work outside of their homes would be thrilled to have an experienced parent watch their children while they are at the office. It can be manageable if your friend in need has only one or two kids. Plus, the new playmates will help keep your children occupied for a few hours. Pay varies widely based on where you live and the ages and number of kids you'll be watching, but babysitters and nannies typically can make up to $10 an hour in small cities and much more – even double that hourly rate – in larger cities.
Buy bottled water in bulk at Costco or Sam's Club and sell it for a dollar where there are a ton of people: parks, festivals, concerts, etc. People are crazy for bottled water and this is a little summertime gig that can bring in more money than you'd think on a hot sunny afternoon. Here's a bonus tip: give some of your proceeds to a charity you care about or that you know will resonate with people. In doing so, you're bottled water business isn't all about your profit. You're helping better our world and also provide a thirsty person some water to drink.
If you have graphic design skills then you could make money online by creating and selling your own design elements, like templates, fonts, graphics, and other assets. This is a great way to earn extra money and build up a portfolio of work, which could lead to you picking up freelance graphic design jobs. Websites like Envato Elements pay you a fee per element sold, which can become quite profitable if your work is popular.
Love dogs, but not ready to get one of your own? Get your fix by taking care of other people’s pooches — and get paid for it. If your home isn’t dog-friendly, consider becoming a dog walker. Apps like Wag! offer on-demand dog walking, so you can pick up walks when your schedule allows. If you have space (and your landlord’s permission, if you rent), offer overnight dog boarding. Dog sitters on Rover.com, the go-to site for pet-sitting, generally command $25 to $35 a night, according to the company.

Small crowdsourcing, online, and real-world tasks, sometimes called  micro jobs, have become an increasingly popular way to pick up extra cash. Short-task websites offer a way for buyers and sellers of services to connect. These gigs generally don't take much effort and, as a result, don't usually pay much. However, if your goal is to earn a few extra dollars, then micro jobs may be just what you need.
If you’ve got some free time and don’t live in the middle of nowhere, becoming a Lyft driver can be a very lucrative side hustle that allows you make money fast. And right now, they’ve got a promotion going on where any new driver will instantly get a $300 bonus after completing their 100th ride. If you start now and hustle hard on the weekends, you can probably unlock that bonus within a few weeks of driving (and that’s in addition to your normal earnings).
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