Son ideales para aplicaciones de Business Intelligence. Como muestra un botón:

El código fuente del ejemplo (copiado de la documentación del API)

    <script type="text/javascript" src="http://www.google.com/jsapi"></script>
    <script type="text/javascript">
      // Load the Visualization API and the piechart package.
      google.load('visualization', '1', {'packages':['piechart']});
      // Set a callback to run when the API is loaded.
      google.setOnLoadCallback(drawChart);
      // Callback that creates and populates a data table,
      // instantiates the pie chart, passes in the data and
      // draws it.
      function drawChart() {
        var data = new google.visualization.DataTable();
        data.addColumn('string', 'Task');
        data.addColumn('number', 'Hours per Day');
        data.addRows([
          ['Work', 11],
          ['Eat', 2],
          ['Commute', 2],
          ['Watch TV', 2],
          ['Sleep', 7]
          ]);
        var chart = new google.visualization.PieChart(document.getElementById('chart_div'));
        chart.draw(data, {width: 400, height: 240, is3D: true, title: 'My Daily Activities'});
      }
    </script>
    <div id="chart_div"></div>