Varolo is a service that is completely free to use, and pays you for watching short ads, and referring others to do the same. Using a few simple methods (all within the site's terms of service) It's very easy to make at least a few hundred a week using the service. They also pay weekly by paypal. They are extremely flexible with the methods of promoting the site. (I have a few that work really, really well. and I'll send them to you on the site as soon as you sign up.)
To start simply go http://varolo.com/village/howitworks, Then click on user tour. After watching the video, the link to sign up is directly below the video.