There are several sites that I use that make me a decent amount of money online for free. One site is a article writing site called associated content. They pay you anywhere from three to twenty dollars an article. I also use survey sites and my two favorite are opinionoutpost and surveyspot. Another great site to write articles for is textbroker. I am also a member of the get paid to complete offer site Cashcrate. All of the above sites are totally free and I have been paid numerous times by them all.
I use something called Neobux. It's a PTC site, it's it's easy as hell. (I am not a bot). I went to some popular forums, and advertised. My buddy is my "sponsor", and he was able to make 80 dollars in 2 days because of the number of refs he has. You can also "buy" refs which are volunteers, or actual people doing Neobux.