Link Indication adds CSS class attributes to external links and optionally specific attributes to any other link types such as wikipedia.org
, flickr, imdb, file extensions like .pdf or .zip, etc. Thereby you can indicate your links, e.g. by images, for characterizing your types of links. Furthermore you can add target="blank" to all external links, rel="nofollow" to specific hyperlinks or display websnapr preview thumbnails.
The plugin is applied at display time, not while a post is being saved. This means that this plugin can be integrated at any time, it will modify the rendering of existing posts and comments as soon as the plugin is enabled.
Please visit the official website
for further details and the latest information on this plugin.