Also, target display mode (on iMacs):

* https://support.apple.com/en-ca/105126

Personally, I wish iMacs had built-in KVMs: with WFH being more of a thing, it'd be nice to have a giant display that I could use for personal stuff (iMac) and work stuff (plug in Macbook, PC laptop), and auto-switch between the two.

(I personally like the all-in-one solutions of iMacs.)

Would be great to be able to boot a beefy desktop computer from my laptop SSD.

I was so envious of my friend's Macs being able to be used as external storage devices that this may have been what convinced me to buy my first macbook nearly 18 years ago.

you might be interested in https://github.com/poettering/diskomator

tldr: bootable image to expose all disks over nvme-tcp.

Note that authentication and encryption is not yet implemented so I would be cautious, but it's still pretty interesting