The extensible nature of widgets and sidebars in WordPress opens those items up to a whole range of possibilities when it comes to making them dynamic. One of the easiest and most noticeable things that you can do is to modify your widgets so that users are able to interact with them. Even the rudimentary interaction provided in this recipe can go a long way to increasing user participation with the site that your theme is deployed on.
First, you need to change the parameters that you are passing to your sidebar registration function. Find the declaration for your sidebar (usually contained within the functions.php file) and change the code to the following:
register_sidebar(array( 'before_widget' => '<li id="%1$s" class="widget %2$s">', 'after_widget' => '</div></li>', 'before_title' => '<h2 class="widgettitle">', 'after_title...