The Anywired blog posts a good guide to using Ubuntu (and most any Linux distribution) productively, through both built-in but under-appreciated features and free software. We've covered a few of the suggestions before, including Compiz Fusion tools, a super-charged Gedit, and app launcher GNOME-Do, but Anywired points out the newest features and offers a few GTD-minded suggestions along the way. As is often noted, however, some tips are Ubuntu-specific, but most can be implemented in any Linux distro. Have your own must-have apps for cranking widgets, open-source style? Let's hear it in the comments.