I only ever used ARexx on the Amiga back when I was a kid and it was amazingly powerful, though I'm not sure how much I'd consider this a function of the langua

I only ever used ARexx on the Amiga back when I was a kid and it was amazingly powerful, though I'm not sure how much I'd consider this a function of the language itself rather than the ecosystem you got when all of your favourite software was built with it in mind. Unfortunately, an ecosystem like that doesn't really exist on the desktop any more, so a lot of the utility is missing. Every now and then I feel an urge to try to mimic the sort of thing that you could do in ARexx easily, only on a modern desktop, and end up having to cobble together some D-Bus monstrosity that is not nearly as fun.