Blogads Ad Network

Blog Ads, located at http://BlogAds.com offers blog writers sell advertising space of their blogs to advertisers who want to get exposure for their products through the network of participating blogs.

The ad formats from Blog Ads are quite attractive, with lot of space for an image and a very long description.

This is not CPC or cost per click advertising. Blog publishers and advertisers can agree upon a rate for publishing the ads. The contract is for a week, a month or for three months. Publishers can review their prices.

Blog Ads take a commission from the price.

Since the advertising space is purchased directly by the advertisor, a publisher needs to ensure that the advertisement will be displayed on a prominent location, mostly top in the page.

It is a bit trickier than Adsense because of the bargain process involved. Also if your blog is not that popular, advertisors will not be interested in your blog.
Signing up for blogads is not open for all, but someone has to invite you to the publisher network (I didn't get an invitation till now).