CNC automotive parts

Hi guys,
Been going down the rabbit hole of CNC automotive parts, and I’m amazed at what people are machining these days — custom valve covers, billet engine mounts, even fully CNC'd intake manifolds that look like alien tech.
I’m thinking of upgrading a few things under the hood, but also curious:
What’s the most over-the-top or oddly specific CNC part you’ve installed? Did it make a legit difference or just make your engine bay look cooler?
If you know a shop that does custom CNC work (not just mass-produced stuff), drop the name — I might have a weird project in mind.
Let’s see those machined masterpieces. Pics welcome.