CSS Sprite Generator : This tool allows you to automate the process of generating CSS sprites. Simply give it a ZIP file containing 2 or more images (GIF, PNG or JPG) and it...
stylelint : A mighty, modern CSS linter that helps you enforce consistent conventions and avoid errors in your stylesheets.
PurgeCSS : PurgeCSS is a tool to remove unused CSS. It can be part of your development workflow.
YAML Builder : A tool for visual layout development of YAML based CSS layouts
csscss : csscss will parse any CSS files you give it and let you know which rulesets have duplicated declarations.
UnCSS is a tool that removes unused CSS from your stylesheets. It works across multiple files and supports Javascript-injected CSS.