If you want long battery life and are running heavy apps directly on the machine, *you're doing it wrong*... Leave the heavy apps on the home (hopefully very large) box and use the ultraportable to remote in. This is how I do all my coding work remotely. With ubiquitous Internet, there's no need to kill battery life by loading up the local CPU and drive. There's also no need to have to maintain multiple install locations of applications. Keep it all on the main PC and use the portable as an interface. I'm getting a solid 9 hours of work time out of my Thinkpad X230 Tablet this way and I don't miss having local apps at all...