Besides crazy specs, like a bunch of RAM, power to do anything at insane speeds, and battery that will last you days...I have had one wish for a while: Being able to take of the screen on my 15" rMBP. The size, weight and design of the current rMBP is great. I would love if I could take the thin and beautiful display(lid) off and use it as a 15" tablet. It would wirelessly receive everything needed from the main body, also the energy to function. A large range, to be able to walk around the house with the display as tablet. Clicking it back to the main body would be easy and seamless.