Cleanest/simplest method to render image fields with Drupal 7

A common issue when building a site in Drupal: you've got a $node, $vars['node'], or $form_state['node'] and need to render an image (with image style) from one of the fields. I am building a custom form in this instance, and need to show the first image stored in some loaded nodes.

  // Get the node loaded via node_load into $node.
  // Use field_get_items to get the correct field data.
  // Use current() to get the first item in the returned array.
  $field_picture = current(field_get_items('node', $node, 'field_picture'));
  // Reuse the field data since it already contains 'alt' and 'title'.
  // Add style_name and path.
  $field_picture['style_name'] = 'image_style';
  $field_picture['path'] = $field_picture['uri'];
  // Render the image to HTML using the field data.
  $picture = theme('image_style', $field_picture);

If you are going to be using the above code often, you should probably put in an function in a custom site module.