I’m typing this post on a MacBook Air – a pretty common device for writers, journalists and other people who need a slim, light and powerful portable computer to get their work done. But how many people do you know who use a computer that’s homing in on ts tenth birthday? My 2011 11-inch MacBook Air is still a great workhorse. Sure, it doesn’t do everything the latest models do. It passes the good enough test but keeping this laptop working has taken some effort.