Google has launched Knol , its Wikipedia alternative that holds authors accountable for the articles they write. Each article is created by a team of authors who receive attribution, and are allowed to take part in a rev-share for AdSense ads on their page.If the visiters click your adsense ads, you get money.More pageviews clicks you get, more money you can get. If you have adsesne account, just write some value posts on Knol, then put your adsense codes, then you make money.
how to put adsense codes on Google Knol? Just following the steps.

1 First of all, you must finish a post.
2  then click  manage:

3 look for Ads in Knol

4 finish adsense form, if you do not have adsesne account, choose create a new adsense account

5 all most finish. after you have finished the form, you can get this page: the status is pending.

6 check your adsesne account email, you will recieve an email from google adsense, there is a link, just click the link, your adsense on knol is avtive.

7 write more articles on knol, more money you will get.