I'm going to have to admit to feeling pretty dumb having just found this out today, especially as I've had a Surface Pro pretty much since its New Zealand launch.
When using a Surface tablet in portrait mode with the keyboard flipped around to the back it's a strange sensation pressing down on the keys as you hold the device. often if I'm using the Surface in portrait mode for any length of time I'll remove the keyboard and use it naked.
Chances are you do too. Don't, there's a trick which is either unintentional or something so obvious that Microsoft didn't think they needed to tell anyone about it.
Unplug your keyboard cover, flip it over and re-attach it upside down. Now when you fold the cover back the keys face the rear of the Surface and your hand holds the pleasing suede cover, which protects the rear of your tablet and is a tactile joy at the same time.
Mind blown! Please tell me I'm not the only one who didn't know about this?