Do you remember those Physics lessons at school with the magnets and the iron filings? Do you remember dripping acid on iron filings in Chemistry lessons?
Surely that has to be the worst job in the world. You turn up at work and there is a big block of iron and your file. That will be your task for eight hours.
The next day:
I wonder what I will be doing today? Oh yes, I remember, filing a big block of iron.