#HTML&CSS autoprefixer - parse CSS and add vendor prefixes to rules by Can I Use.
grunt-browser-sync - keep multiple browsers & devices in sync when building websites.
grunt-html-build - appends scripts and styles, Removes debug parts, append html partials.
grunt-email-design - a workflow for designing and testing HTML email templates.
grunt-uncss and grunt-ucss - remove unused CSS from your projects.
grunt-contrib-cssmin - compress CSS files.
grunt-revizor - compress CSS classes and identifiers.
grunt-contrib-htmlmin - neat HTML minificator.
grunt-penthouse and grunt-criticalcss - automatically find the Critical Path in your project.
grunt-csscomb - refines the structure of your CSS.
grunt-styleguide - generate styleguides.
grunt-contrib-csslint - CSS linter.
grunt-html - HTML validator based on validator from W3C.
#JavaScript grunt-autopolyfiller - precise polyfills. This is like Autoprefixer, but for JavaScript polyfills.
grunt-jsfmt - for formatting, searching, and rewriting JavaScript.
grunt-jscs - for checking JavaScript Code Style.
grunt-modernizr - build out a lean, mean Modernizr machine.
grunt-contrib-requirejs and grunt-browserify - optimize the work with RequireJS and Browserify respectively.
grunt-wiredep - inject Bower packages.
grunt-plato - generate static analysis reports.
grunt-complexity - evaluates code maintainability using Halstead and Cyclomatic metrics.
fixmyjs - automatically fix silly lint errors with help of JSHint (grunt-contrib-jshint).
grunt-jsonlint and grunt-yamllint - JSON and YAML validators.
grunt-contrib-uglify - JavaScript compressor.
grunt-contrib-concat - concatenate files.
###Unit Tests
#Graphics grunticon - mystical CSS icon solution.
[grunt-webfont](SVG to webfont converter) - SVG to webfont converter.
grunt-responsive-images - produce images at different sizes for responsive websites.
grunt-sharp - fastest module for work JPEG, PNG, WebP and TIFF images.
grunt-svgstore - merge SVGs from a folder.
imacss - application and library that transforms image files to data URIs.
grunt-contrib-imagemin, grunt-imageoptim and grunt-tinypng for image compression.
grunt-spritesmith - converting a set of images into a spritesheet and corresponding CSS variables.
#Others assemble - static site generator.
jit-grunt - JIT(Just In Time) loader.
grunt-gulp- allows to start Gulp plugins for Grunt.
grunt-contrib-watch - run tasks whenever watched files change.
grunt-notify - automatic error messages in system notifications center when Grunt tasks fail.
grunt-git - able to use Git commands.
grunt-githooks - bind Grunt tasks to Git Hooks.
grunt-gitbook - create documentation by GitBook.
grunt-jsdoc - generate JavaScript documentation by running JSDoc3.
grunt-conventional-changelog - generating a changelog from Git metadata.
grunt-remove-logging - remove console logging statements.
node-matchdep - filter npm module dependencies.
grunt-phantomas - measure frontend performance.
grunt-preprocess - preprocess files based off environment configuration.
grunt-rev - useful plugin to work with versions.
grunt-open - open URLs and files.
grunt-contrib-connect - simple static web server.
grunt-exec and grunt-shell - run Shell commands.
grunt-ssh - provides the ability to connect via SSH and SFTP.
grunt-contrib-compress - compress files and folders.
grunt-contrib-clean and grunt-contrib-copy - respectively remove and copy sources.
#Compilers
- grunt-contrib-less - LESS in CSS.
- grunt-contrib-sass - SASS/SCSS in СSS.
- grunt-contrib-compass - SASS with Compass in CSS.
- grunt-contrib-stylus - Stylus in CSS.
- grunt-contrib-coffee - CoffeeScript in JavaScript.
- grunt-contrib-jade - Jade in HTML.
- grunt-contrib-handlebars - Handlebars templates in JST.
- grunt-contrib-jst - Underscore templates in JST.
- grunt-react - Facebook React's JSX templates in JST.
- grunt-nunjucks - Nunjucks templates in JST.
- grunt-dustjs - Dust templates in JST.
- grunt-html2js - AngularJS templates in JST.
#Finally
- psi - PageSpeed Insights with reporting.
- tmi - TMI (Too Many Images) - discover your image weight on the web.
- ngrok - Introspected tunnels to localhost.
- pageres - responsive website screenshots .
- Maybe some automatization methods you want to use directly in the editor, so look at the The Best Plugins for Sublime Text.