<?php
 
 
$bigArray = array(
	'name'=>'one', 
	'something'=>array(
		'name'=>'two', 
		'subthing'=>array('name'=>'three')
	), 
	'anotherthing'=>array('name'=>'one')
);
 
$uniques = array();
$indirect = array(&$uniques);
 
function singleOut($item, $key, $indirect) {
	$uniques=&$indirect[0];
	if ($key == 'name' && !in_array($item,$uniques,true) ) $uniques[] = $item;
 
}
 
array_walk_recursive($bigArray, 'singleOut', $indirect);
print_r($uniques);
 
?>

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