How it started
Free Incentive sites really started to get going a few years ago, a company called Gratis Internet started the ball rolling with the very famous incentives site called FreeIpods.com. This site was restricted to US residents only, since then other companies have set up there own incentive sites.
Types of Incentive Site
There are 3 main types of incentive site. With referral based sites such as Freebiejeebies you complete one offer and then get referrals to earn a gift. With point based sites such as Giveaway Central you can complete as many offers as you want as well as get referrals to earn gifts, because sites like this can be completed without getting any referrals the number of points needed is usually a bit higher. With Cash based sites (no that common) users earn cash for each offer they complete and sometimes for each referral they get.
How they work
Many people that think these sites are scams do so because they don't understand how the incentive site can afford to give away such expensive gifts for free. Well companies such as LOVEFiLM and AOL pay the incentive site owners a fee for getting you to try out there service in the hope that you will carry on with there service after the trial. When you add the fee they get for you for doing a trial to the fees they receive for all the referrals you get it quickly adds up to more than the cost of the gift. Everyone is happy, you because you have got your gift for free, the trial owner because they have had a possible customer try there service and incentive site because they have made a little profit on top.
Yes there are some scam sites out there. Before I add any incentive site to 4Free4U I do research into there credibility of them, so rest assured any site you sign up to through 4Free4U will be safe.