If you have a file sharing or downloading website, there's a great way to monetize a blog or a website - use a content locking system. It is a revolutionary system which can help you make tons of more money with the same content and traffic. Here's how it works: You can install a very simple script which basically locks your content page. Every time someone visits that page, the visitor will only be able to see the content after he or she has completed a simple action such as a form fill or a survey. It's a fairly new technique. You can check out some details here for one of the systems that I use on one of my blogs. It is new but seems quite promising (I have made about twice the money than I did from Adsense in a couple of weeks).
I am not sure..I was looking for that in the rules but couldn't find it. If any of the mods see this, can they let me know? I will remove post.
Content locker do generally yield more revenue than adsense but the technology has already been out for 3-4 years. It's not really new.