We all know how cool and useful Thunderbolt 3 is.
That gives me an idea. Why not connect a Thunderbolt dock to an old sucky laptop, add an external GPU, an external monitor, an external CPU, external peripherals.
Basically giving the laptop an upgrade without actually upgrading the inside, but using external hardware to do so.
I've zero idea if it would work and even if it does, how it would perform. Nonetheless, it'd be really really cool.