If you need to make a complex part, BUT you're in a submarine 500 feet down, you definitely need one of these machines

 I'm not suggesting anyone try to buy one of these, I just think it's an absolutely fascinating machine.

https://www.lathes.co.uk/hommel/
(the site needs white space and he's wordy - too much detail core-dumped at once IMNSHO; it would benefit from a more modular / chapterized approach.)

An extraordinary machine, built to very high standards for accuracy and precision.  By using the base and column to mount combinations of a headstock, tailstock, compound slide rest, T-slotted boring table, rotary table (and numerous other accessories) the assembly could be used as a plain-turning or screwcutting 3.5 inch (90 mm) centre height by 14 inches (360 mm) between-centres lathe, high-speed sensitive drill, vertical and horizontal miller, jig borer, shaper, gear cutter, grinder, engraver, slotter, metal saw or surface table.

A Smithy can only *wish* it had a UWM in its lineage -- these things are special and unique with far greater versatility, precision, and accuracy, vs. a Smithy.  I'd be willing to bet it could be set up to be a drill / milling cutter sharpener.  Just need the right wheel.

The UWG1 (alone, not counting all accessories!) is small enough to fit on top of your shop's beer fridge.  The footprint is smaller than a Smithy.

The UWG2 is the same machine but larger footprint/capacity.  All accessories and tools swap between the two sizes of machine.

 These machines were designed to be an "Eierlegende Wollmilchsäue" or, literally translated, "egg-laying wool-milk-pig" - a machine that could do everything.
(everything that can be done in a tight space, that is - they went onto warships and submarines, even airplanes and ground mobile repair units.)

They are not perfect - warts and goblins are detailed at the page linked above.

There is a German language site with more information, but it's insecure and has eight or nine open vulnerabilities so I can't recommend it. :(

The machines themselves are breathtakingly expensive when they appear on the market at all, and there are a LOT of accessories in the complete tooling set.  Most machines are not sold with everything present.  A single base plate part is on Ebay for $700.  Complete machines can be found more often in Europe, where they sell for $3500 - $5000.  You can buy  a brand new full sized Chinese knee mill with DRO, vise, oiler, everything turnkey, for that price.  You can have it shipped from China to your door for another grand or less.

 So paying that amount for a weird little machine that dates from before WW-2 might be a stretch for most people I know.  Definitely a niche market. :)

And changing it from a mill to a lathe and so on is fiddly and time consuming.

 ~≈{👁}≈~