To date one of the finest repurposings I’ve seen: At a car repair
shop, a rear axle assembly has had one shaft removed, and had an
electric motor fit on to the end of the still-connected driveshaft
(where the transmission assembly used to sit). What is left of the
axle assembly, valued for its ability to spin at high speeds, now
functions as the primary component in a machine for porting cylinder
heads in worn-out engines. A relatively low-cost solution, and ideal
for an environment where resource constraints rule the day.

The brave sacrifice of an axle so that +40-year old Mazda B1500
engines may continue to serve. Almost brings a tear to my eye.