Yes, it's pretty easy. Create an event module:
http://www.question2answer.org/modules.php#event
and have it check for q_post, a_post, and c_post, then have it call the function:
qa_send_notification($userid, $email, $handle, $subject, $body, $subs);
where $subs is an associative array that substitutes keys for values in $body, e.g.:
$subs = array(
'^badge_name'=> qa_opt('badge_'.$badge_slug.'_name'),
'^post_title'=> @$post_title,
'^post_url'=> @$post_url,
'^profile_url'=> $profile_url,
'^site_url'=> $site_url,
);
Or, you can also just create a custom $body on the fly. See the badges plugin for an example.
