How do I use a field summary in a view?
I think this is a good example for using custom formatters.

I Recommend you to use the custom formatters module as you cant get a fast result, but if you think this is useful, you should check the Field Formatter API to make more complex sollutions.

Install the module, and import this example:

$formatter = new stdClass();
$formatter-&gt;disabled = FALSE; /* Edit this to true to make a default formatter disabled initially */
$formatter-&gt;api_version = 2;
$formatter-&gt;name = 'test_body';
$formatter-&gt;label = 'test body';
$formatter-&gt;description = '';
$formatter-&gt;mode = 'php';
$formatter-&gt;field_types = 'text_with_summary';
$formatter-&gt;code = '$output = "";
foreach ($variables[\'#items\'] as $item) {
  if ( $item[\'summary\']) {
    $output = $item[\'summary\'];
  }else{
     $output = $item[\'value\'];
  }
}
return $output;';
$formatter-&gt;fapi = '';


it doesn't do all the job, but i think it can be enough for you to complete it.

Then go to your view and select the formatter for the body field.