Although this technique is as old as the hills, the main advantage here is to make people really want to pass your reports to their friends.
The basic concept of this old method is to offer a free book on your website, and if someone wants to download it, he just has to post his email address to your sign up form - opt in form - and the he will receive the download link on his inbox.
In addition, there is another part of this old method by including an affiliate links related to your report within it, so you will gain a commission when people buy those related products.
The best thing when developing your traffic plan is to trying to get the most of everything possible, and the method I will explain here is a perfect model on this rule.
Now you have to give your visitors the same report with the same affiliate programs, but with one change, and it is by making these links customizable, you can perform this task by using special software called "PDF Brander".
In this case, this will allow the others to change their affiliate links with yours, but the question, what are the additional benefits of using this technique? Now, you have many of persons that they spread your report with their affiliate links to make money of them, so when a good number of them have not affiliate products related to your report, then you could still benefits from your affiliate links and collect a second-tier commission, because they become an affiliate under you.
If you leave some of backlinks to your website home page, this might give you another potential site visitor even all your affiliate links have changed.