多选插件multiselect.js

html：

<html>
  <head>
    <link href="path/to/multiselect.css" media="screen" rel="stylesheet" type="text/css">
  </head>
  <body>
    <select multiple="multiple" id="my-select" name="my-select[]">
      <option value='elem_1'>elem 1</option>
      <option value='elem_2'>elem 2</option>
      <option value='elem_3'>elem 3</option>
      <option value='elem_4'>elem 4</option>
      ...
      <option value='elem_100'>elem 100</option>
    </select>
    <script src="path/to/jquery.multi-select.js" type="text/javascript"></script>
  </body>
</html>

JavaScript：

$('#my-select').multiSelect();
$('#my-select').multiSelect({ keepOrder: true });//按添加的先后排序

获取选中的值（移到右侧的值）的方法：

$('#my-select').val();