My basic Gruntfile.js - used to copy files form development to deploy, set-up sass/compass, uglify js, jshint, compress css and watch all files / folders.

Gruntfile.js

module.exports = function(grunt) {
 
    // Project configuration.
    grunt.initConfig({
 
        //Read the package.json (optional)
        pkg: grunt.file.readJSON('package.json'),
 
        // Metadata.
        meta: {
            basePath: '',
            srcPath: 'js/',
            deployPath: 'deploy/'
        },
 
        
        // ==================================
        // TASKS CONFIG


        // COPY FILES FROM SOURCE TO DEPLOY - https://github.com/gruntjs/grunt-contrib-copy
        // don't include '!X'
        copy: {
            deploy: {
                expand: true,
                src: ["*", "css/*", "css/fonts/*", "js/*/**", "!css/scss", 'js/*.js', "!node_modules", "!Gruntfile.js", "!package.json", "!deploy", "!doc", "!src"  ],
                dest: 'deploy/'
            }
        },

        // COMPASS / SASS - https://github.com/gruntjs/grunt-contrib-compass
        compass: {                  // Task
          deploy: {              // Target options
            options: {
                sassDir: 'css/scss',
                cssDir: 'css',
                fontsDir: 'css/fonts',
                outputStyle: 'compressed',
                noLineComments: true
            }
          }
        },


        // MINIFY - https://github.com/gruntjs/grunt-contrib-uglify
        uglify: {
            deploy: {              // Target options
                options: {
                    banner: '/*! <%= pkg.name %> - v<%= pkg.version %> - ' + '<%= grunt.template.today("yyyy-mm-dd") %>\n' + '* Copyright (c) <%= grunt.template.today("yyyy") %> '
                },
                my_target: {
                  files: {
                    'js/main.js': ['js/main.js']
                  }
               }
           }
        },

        // JSHINT - https://github.com/gruntjs/grunt-contrib-jshint
        jshint: {
            deploy: {
                all: ['js/**/*.js', 'js/*.js']
            }
        },

        // CONNECT - Create server - https://github.com/gruntjs/grunt-contrib-connect
        connect: {
            server: {
              options: {
                port: 8080,
                base: 'deploy'
              }
            }
        },

        // WATCH FILES & FOLDERS - https://github.com/gruntjs/grunt-contrib-watch
        // Executes the listed targets on file save
        // Watches folders for file changes and then runs the specified tasks
        watch: {
            jshint: {
                files: ['js/**/*.js', 'js/*.js'],
                tasks: ['jshint:deploy'],
                options: {
                    interrupt: true
                }
            },
            compass: {
                files: 'css/scss/*.scss',
                tasks: ['compass:deploy'],
                options: {
                    interrupt: true
                }
            },
            copy: {
                files: ["*", "css/*", "css/fonts/*", "js/*/**", 'js/*.js', "!css/scss", "!node_modules", "!Gruntfile.js", "!package.json", "!deploy", "!doc", "!src"  ],
                tasks: ['copy:deploy'],
                options: {
                    interrupt: true,
                    nospawn: true
                }
            }
        }

    });
 
    // These plugins provide necessary tasks.
    grunt.loadNpmTasks('grunt-contrib-uglify');
    grunt.loadNpmTasks('grunt-contrib-compass');
    grunt.loadNpmTasks('grunt-contrib-copy');
    grunt.loadNpmTasks('grunt-contrib-watch');
    grunt.loadNpmTasks('grunt-contrib-jshint');
    grunt.loadNpmTasks('grunt-contrib-connect');

    // Resigster tasks in order
    // Make sure WATCH is last
    grunt.registerTask('default', [ 'compass', 'jshint', 'copy', 'uglify', 'connect', 'watch']);
 
};