Not all are scams. But you must be carefull.
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Top Internet Job Search Job Scams 2014
By Alison Doyle
There are a variety of internet job scams, ranging from fake jobs, to scams that try and collect your personal information, or ask you to send money or make purchases for them. Here's a list of online scams shared by About.com readers ...

While thinking about making money, it’s also important to note how to avoid losing it too. While there are many legitimate ways to make money at home, there are also plenty of SCAMMERS out there too. Christine Durst, author of The Rat Race Rebellion, says her research indicates the ratio of scams to legitimate opportunities is 42 to 1.

Home agent
A home agent is a catchall term that includes tasks like phone sales, market research, customer service and tech support. In other words, it's any job that you would normally do in a large call center with hundreds of other people, but you do it from home ...

Freelancer
For those skilled in creative or technical areas like graphic design, video and image editing, writing or programming, you can try the life of a freelancer. There are plenty of job boards expressly for freelancers and people who WANT to hire them.
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E-book author
If you can write, but don't want to write for someone else, being an e-book author might be the job for you. With publishers getting $3 billion in sales on e-books last year – and that doesn't include self-published e-books – there's definitely money to be made..