Ever heard of Smorty? No? Neither did I until i stumbled across it. Smorty is a online service that allows bloggers to advertise other advertisers products and get paid for doing so. The service is totally free to join up. The amount you earn through the program depends on your page rank, popularity and search engine indexing.
If you wish to advertise your products and have bloggers make reviews of your content, then you must sign up for a advertising account, which will allow you to advertise on blogs all around the internet.
Also if you wish to advertise other products and get paid for it, then a blogging account is what you need. It's free to sign up and you must make sure your website is in Google and Yahoo search engines, your blog must also be over 3 months old, non adult and it's preferred language as English.
I have just started using the service and so far I personally have 5 items in my pending list, so there is great potential here to earn money by blogging.