http://www.micahcarrick.com/09-29-2007/gedit-html-editor.html
A nice article on how to mod the hell out of gedit to make into a pretty powerful ide. Some really good plugin recommendations and some custom code. Nice job. :-)
http://www.tuxfiles.org/linuxhelp/vimcheat.html
A vim cheat sheet. Lists various commands in one page, easily searchable.
http://live.gnome.org/Gedit/Plugins
A list of plugins available for Gedit. Useful resource.
http://www.alexyoung.org/articles/show/12/vim_for_textmate_fans
An article on tuning vim to be more like Texmate (proprietary mac text editor). Discusses code completion, plugins, and a few other cool tips.
http://grigio.org/pimp_my_gedit_was_textmate_linux
A post on pimping Gedit to make is something like Textmate (proprietary mac editor). Includes tips on some useful plugins and how to tweak settings. Worth checking out.
http://tips.webdesign10.com/editors-for-ruby-on-rails-ubuntu-jedit-emacs-radrails-cream-scite
An overview of various editors for Ubuntu Dapper, focusing on Ruby on Rails compatibility. Each editor is covered in a little detail with enough information to get a flavour of it. Useful.