Link Wrench is a WordPress plugin that wraps the content of the links (anchor tags) in your blog in a span with class "insidelink".
Link Wrench wraps the content of the links (anchor tags) in your blog in a span with class "insidelink". You can then use CSS to style them.
Development of the plugin is on github.
This plugin is funded by StrawberryCat.
Download the zip then upload it to your blog from the Add Plugin menu.