I joined a site called myfreeshares after hearing about it from a friend. At myfreeshares you earn shares for clicking links and joining other GPT programs. The revenue that is generated from the site is then paid out to members according to the share value. Their advertising options are nice and for every dollar you spend you get 2 shares. I've purchased 100 referrals from them in all and spent about $50. That's a pretty good price if you do some price comparison on the web.
The problem with systems like this is that your purchased referrals are only signing up for your program to recieve an incentive, shares in this case. Most recently I purchased 50 shares for $25 dollars for a website called It Pays To Learn (hopefully it does). Out of those 50 referrals so far I've recieved 24. Out of the 24 purchased referrals, only 10 have even bothered to login to the site after registering! Of the 10 people that registered and logged in, I'm estimating only 2-3 are actually active.
Don't get me wrong. Myfreeshares is a great sight. Their customer service is excellent and ranks up there at the top. The concept of purchased referrals where incentive is given to sign up for a site that they probobly have no plans to be active in is where the problem occurs.
On the other hand after 10 days of being registered at ItPaysToLearn, I've already earned $2 and that's not bad for just getting started!
So, Keep an eye out for purchased referral systems where referrals might only be signing up for the incentive. These results are definately going to vary from site to site. Hopefully things will pick up and these referrals will get the ball rolling. I'll be sure to update again with more stats in the future!