Something new from Google AdWords.
It’s now possible not only to set your maxium bid for each keyword but your preferred average cost per click. Through some kind of bid management Google places your ad in a range of positions according to your preffered average click price.

Preferred cost bidding is an advanced bidding option available for keyword- and site-targeted campaigns. If you identify with the following goals, preferred cost bidding may be the right bidding strategy for you.

* I know how much each click or impression on my ad is worth to my business. (Learn more about determining the worth of clicks or impressions.)
* I would rather target an average cost per click or thousand impressions, rather than specifying the most that I am willing to pay.
* I want my AdWords advertising costs to be more consistent, rather than changing from day to day.
* I do not want to constantly monitor and adjust my bid settings. Within the budget that I set, I want Google to take care of my individual keyword or site bids.