public static function unorderedList( $items, $level = 0, $attributes = array() )
	{
		$depth1		= 2 * abs( (int) $level );
		$depth2		= $level ? 2 * abs( (int) $level - 1 ) + 1 : 0;
		$indent1	= str_repeat( "  ", $depth1 );
		$indent2	= str_repeat( "  ", $depth2 );
		$content	= "\n".implode( "\n", $items )."\n".$indent1;
		$tag		= UI_HTML_Tag::create( "ul", $content, $attributes );
		$code		= $indent1.$tag."\n".$indent2;
		return $code;
	}