public function get($key) {
		// First, check to see if the result has been cached.
		if (!isset($this->_cache[$key])) {
			return FALSE;
		}

		// Second, check its freshness.
		if ($this->_cache[$key]['time'] < time() - self::$_lifespan) {
			return FALSE;
		}

		return $this->_cache[$key]['data'];
	}