Nothing that visionary or even self aware, but imagine a giant sphere, sealed with an inside vacuum and also coated on the inside with IC's connected via copper

Nothing that visionary or even self aware, but imagine a giant sphere, sealed with an inside vacuum and also coated on the inside with IC's connected via copper for power and basic communication but each IC also had a nodule/transceiver that could communicate with every other IC via the light spectrum, because every IC had line of sight to the others, all submerged in liquid nitrogen or some other coolant. The premise was a giant campus like a school that users would be able to carry near-dumb terminals around, like smartphones with very little power but if they needed computational power all they had to do to tap into the sphere, by being in visible range of receptacles all around the campus both inside and out. And the sphere could borrow processing power from unused devices if they were available. So light was the practical connection for users, but also used inside the sphere.