While visiting many of the daily blog, i found that most of the blogs are now a days conducting free contest and giving away money in Dollars through Paypal.
A blog titled "Blog Contest: Win $60 In Cash By Participating In The Contest", showing that he is conducting a contest where he said to follow some assignment should be followed like : Subscribing to RSS feed for 1 points, ReTweet this post using Re Tweet (Green) Button near the post title for 2 points, Post on Facebook wall using Facebook post button near the title for 1 point, Publish about the contest in your blog post 3 points. These all are for the blog promotion and in the exchange they will give a prize of money.
The free way of organizing blog contest is just the cheapest way of Advertising over various blog's posts. Increasing backlink with conducting contests is easy!! This makes the readers more interested in getting a free contests, so as a good content of the blog.
Benefits of the contest referrer's blog:
The referrers who inform their readers about the contest through their blog, indirectly gives its user a good content. Most user too like to know about any free contest.
Another type of contest, where the users were asked to comment on that blog with 10-20 words with good speak. The selectd the user number of the user will win the contest.
I am really thinking to conduct a contest within 3-4 months with a good amount of money!!