Here's a useful Drupal module that tweaks a node's body or teaser to insert an inline AdSense ad, when a node is rendered on a full page or teaser list.
This allows site administrators to enable automatic insertion of an AdSense ad into the page without the content editor having to insert inline [adense] filter tags, or having to edit a site's template.php (or other template files.) This offers a big advantage, as you can change the ad format, group, and channel on the fly without hand-editing each node (which is the only way I can think of doing it if you are using inline filters). Another advantage is that you can enable/disable the inserted AdSense with just a click of the mouse - no need to edit each node.