Sure it could, hypothetically. It wouldn't be exactly fashionable or portable - think gargantuan Dell "portable workstations" instead of Macbook Airs - but it's hypothetically doable.

And quite honestly, I'd be willing to sell my home and live in my car for the next decade or so in order to afford such a beauty should someone try and make one. Especially if it had some high-end GPUs wired directly into it via CAPI. Its battery life would be 4 seconds long, it would weigh more than a Ford truck, and it would run hot enough to cook my breakfast in the morning, but god damn would it be worth it.