Here's an interesting rabbit hole to go down.
Why use silicon chips when you can use actual brain cells for computing (aka organoid intelligence)?
These Living Computers Are Made from Human Neurons | Scientific American
And this is a bit old, but yes, OI can learn to play pong:
I'll admit that combining human cells and computers weirds me out a little (though that might be a gross oversimplification of what's actually happening here), but this is still a pretty cool experiment.
In reply to Colin Wood :
That basically sums it up. Human cells use far less energy than conventional chips, but they don't seem to last very long. I'm curious how this will play out.