With the cheaper electric Excavators getting more common, it'd be pretty cool to see one of these get built. Right now making conveyer belts seems to be a big thing. If your machine doesn't dig well in crumb rudder or real dirt, you could still make something more useful out of it.
https://m.youtube.com/watch?v=bsvCc6bX-bk
Mobile conveyer belting system mounted on an Excavator.
It's kinda similar to the old Barber&Greene loaders / Adams Travelloaders.