> Of all the keys on a modern keyboard, I can't think of any possible use for Scroll
> Does it actually do anything these days (outside of Mame, ofc)?
I use it on Excel so I can move/view across the sheet without moving the cursor position, there should be other software somewhere with a similar function.
I also use it as a replacement for Right Crtl hot-keys on VirtualBox when applicable. When gaming on virtual machines you need both Crtl keys available.