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.