AngularJS Example:

by beltiste

HTML

<div ng-app>
  <h2>Todo</h2>
  <div ng-controller="TodoCtrl">
    <span>{{remaining()}} of {{todos.length}} remaining</span>
    [ <a href="" ng-click="archive()">archive</a> ]
    <ul class="unstyled">
      <li ng-repeat="todo in todos">
        <input type="checkbox" ng-model="todo.done">
        <span class="done-{{todo.done}}">{{todo.text}}</span>
      </li>
    </ul>
    <form ng-submit="addTodo()">
      <input type="text" ng-model="todoText"  size="30"
             placeholder="add new todo here">
      <input class="btn-primary" type="submit" value="add">
    </form>
  </div>
</div>

CSS

</style> <!-- Ugly Hack due to jsFiddle issue: http://goo.gl/BUfGZ --> 
<link rel="stylesheet" href="http://twitter.github.com/bootstrap/assets/css/bootstrap.css">
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.0.8/angular.min.js"></script>
<style>
.done-true {
  text-decoration: line-through;
  color: grey;
}

CoffeeScript

TodoCtrl = ($scope) ->
  $scope.todos = [
    text: "learn angular"
    done: true
  ,
    text: "build an angular app"
    done: false
  ]
  $scope.addTodo = ->
    $scope.todos.push
      text: $scope.todoText
      done: false

    $scope.todoText = ""

  $scope.remaining = ->
    count = 0
    angular.forEach $scope.todos, (todo) ->
      count += (if todo.done then 0 else 1)

    count

  $scope.archive = ->
    oldTodos = $scope.todos
    $scope.todos = []
    angular.forEach oldTodos, (todo) ->
      $scope.todos.push todo  unless todo.done