IDK, we have all of the unused space behind the screen of a laptop. Why are there no attachable modules that take advantage of that?

It would be ideal to have a PCIe Thunderbolt connector that allows you to attach a GPU that maglocks to the back of the screen while in use, and any manufacturer could make their own variations. Thunderbolt can easily send 100w of power. Wouldn't be on desktop scales but it would be enough to make me happy.