>least of all on the Wii's IO processor.
The Wii sold well, thus, if anything, it is a particularly good target for playing with Jazelle.
I was approaching it from the perspective of "What would be useful to do on a Wii?" When you approach it from the perspective of "I want to play with Jazelle - what can I use?" it makes much more sense. Thanks.
EDIT: Following one of the reference links, apparently you can enter Jazelle mode on the Nintendo 3DS's application cores. That's another suitable target. https://github.com/SonoSooS/libjz
Philosophical question: What does "useful" mean in the context of a game console?
In my view, it's people having fun with it and maybe learning a new thing or two, so I'd say this is as useful as it gets.