Not really a computer but some distributed systems already work that way. I've read somewhere that Netflix (might have been Amazon?) is designed in such a way that it's capable of satisfying certain requirements even when services are down.
It's easy to continue working at increased costs when you don't have a cache. That's.. that's what a cache is for; it's not critical to the infrastructure, it's here to reduce the costs.
Not to rain on any parade of course, I'm just pointing out I'd like to see more cases of actual plasticity of an email server that puts all jobs on hold while it temporarily takes over for a database server that just stopped responding.
The motor cortex is still doing its original job, it just has to work harder.
So, sort of.