Have a knack for a certain subject and live near a college? Consider offering up your brain power and teaching skills for some quick cash. Grade school kids need help too, and parents pay better than college students. You can take this idea to the next level and scale by tutoring online. We have an interview post dedicated to a chemistry tutor who took his skills to Tutor.com. To be successful, you have to have a good grasp of the concepts but also be able to find a way to relate topics using real-world examples.
Better yet, you can even upload your own book to one of the world’s largest book sellers: Amazon. With Amazon self-publishing, you set the price, retain the rights to your book, and get access to Amazon’s massive audience. For every sale, you keep 70% with Amazon taking the remainder as a fee. If you want to get started, check out Leslie Samuel's great guide to selling eBooks online or follow Tara Gentile on CreativeLive as she shows you how to use your existing body of work to write an eBook within the next week. Who knows, you might just write one of the best business books of this year!
You'll have to leave your house for this one, but hospitality consulting firms like Coyle rely on secret shoppers to evaluate their clients' services. Sign up to be an evaluator and you could get paid to receive spa treatments, dine at restaurants or stay at a hotel. There are lots of opportunities in other fields, too, ranging from entertainment (hello, amusement parks!) to automobiles. However, watch out for scams; check the MSPA for a list of legitimate mystery shopping companies. Earning potential: About $10 per hour
If you have a good idea for an app, and the skills to create it, then producing your own premium app can be profitable. However, with so many free apps available, it may be hard to convince people to pay. If you want to go down the premium app route, consider having a basic free version to encourage people to download the app in the first place. You can then provide the option of upgrading to a premium plan once users realize how useful the app is.
Donating plasma can actually work out better than selling your blood. It takes longer to donate plasma because they will put your red blood cells back in your system. The upside is that you can donate plasma as much as twice a week and you can make anywhere from $40-$60 per donation. You can make that $100 in less than a week if you can stomach the needle.