I’ve been pretty lucky with jobs, but here are the lowlights
Working on a research farm, harvesting and handling rapeseed. It was over a summer and paid £3 per hour, £4.50/hour once you’d done 40 hours that week, so we all worked like 60hours. Mostly it was ace, outdoors, messing about in huge silos of tiny seed, but some of the crop was in the greenhouses which was diabolical. Everything was covered with powdery mildew so we had to wear full breathing gear and environmental suits and even then the stuff got through and caused mega mega hayfever reactions. Never want to smell greenhouse grown oilseed plants and powdery mildew again. EVER.
In the kitchens at Addenbrookes hospital in Cambridge. Stood by the gaping maw of an industrial dishwasher taking out plates and cutlery that felt hotter than the surface of the sun whilst it hissed and spat at me.
Most of the repetitive jobs (like stuffing envelopes) I’ve had I’ve not found boring cause I can just wonder off in my head or chat with co-workers.