Many of our users have made plugins for various editors which are listed on the plugins page.
Gustavo Vargas has written a Django plugin which allows you to use both cssminifier.com and javascript-minifier from within your projects.
Jon Toffy made a plugin for the Krusader File Manager.
Tony Almeida made a PHP Library - PHP-JS-CSS-Minifier - to help minify both CSS and JS files in your PHP projects. Thanks Tony!