Update: The new Pay with a Like WordPress Plugin has now been released!
As we noticed that there is a need for this plugin, we developed it and it is now ready for beta tests.
What does this plugin do? It simply hides part(s) of your post/page content until it is "like"d by the visitor. For liking, Facebook, Linkedin, Twitter or Google +1 can be selected. When it is liked, visitor is now free to see (or download) the hidden content for the adjustable cookie validity time.
You can select to protect a single, some or all of your posts/pages and even you can select to hide more than one part of your post/page.
It supports custom post types too!
No registration to the website is required. Settings are similar to PPV (Pay Per View) and actually both plugins can work in combination: You can have some part of your content protected/hidden to be revealed with $ payment, and other part(s) to be revealed with Likes.
Some other features:
Sitewide like: Admin can select to reveal all protected content on the website after a single like
Selectable random and single urls to be liked: Default setting is liking the page that the button is clicked, but admin can select a specific page (e.g. home page) or a random published post/page to be liked. The latter one may be preferred for SEO reasons.
To use less resources, this plugin does not refer to the database to check if visitor actually liked the content, but it uses a cookie. Cookie is encrypted using website specific "salt". Therefore it is almost impossible to deceive the plugin to reveal a content without liking.
Please have a look and give us your feedback