In my opinion adsense (google adsense) but firstly you have to make a web site and you have to be approved by them. If you don't know how to make a web site, make a blog it's easyer and tehre are a lot of templates. (You will do it online, without any difficult programs).
Write high quality content. companies are looking to hire copywriters and pay anything over $2500 for a single sales page. I know three guys who charge more than $30,000 for a single sales letter. Just imagine, the earning opportunities for a copywriter.
If u have more time, you can go for pay to click sites, google adsense, taking surveys, some good forums tht can requests services! but before u join anything, make sure it is not scam and doesn't require any initial payment
it depends of what you know to do. for example, if you know how to write articles, you could earn about 1000 dollars per month. or, if you would like to be sex-videochat performer, you could earn more than 5000 us dollars per month.
