While it is not shape-shifting, I’ve experienced a touch screen where you actually could “feel bumps”. Depending on your fingers position, it vibrates in a way that makes you “feel” a bump or ridge. It was amazing.

Like entering a PIN: You close your eyes and put a finger on the screen. The code centers a numeric keyboard at this position so you are on the “5”. You can move your fingers up, and you can feel a “ridge” when moving to the “2” field. You move left and feel a ridge when moving to the “1” field. If you move back to the “5”, you can feel the “bump”, and it differs from the feel of the “ridge”. Once you are on the right field, you lift your finger and bring it down again to select this number. If you leave it off a bit longer, it just re-centers the keypad to the “5” position.

Of course this only works with one finger, but it is absolutely amazing how convincing this is, especially if you close your eyes.