With a plugin, of course.
(Save the content into a file called adhesive.php and upload/activate like any other plugin.)
Unfortunately, Owen stopped developing the plugin (I think) because he's moved from helping with the WP project to working on a fork called Habari.
So, as of this writing, it appears the plugin stopped at WP 2.0.x; it may, however, still work with versions up -- but you can't say you haven't been warned.
~ Teli