World’s Smallest V-12 Engine

A Spanish engineer known as Patelo has created what he says is the world’s smallest V12 engine, crafting 261 pieces — everything but the screws — from scratch.
The impressive process took 1200 hours, including design, milling and drilling the parts, and assembling the whole thing.
To give you an idea of how small the mini-V12 is, its pistons are less than half an inch in diameter.
Check out the video on the link to see this thing being built.