I don’t keep them on the bike, but I will always have a vessel impacta screwdriver in my toolbox. It’s a JIS style tip, with built in impact driving for getting things loosened up. I think it’s definitely a must have for anyone that works on vintage Japanese bikes.
https://www.vesseltools.com/handtools/screwdrivers/impact/980-series
Yep. Grew up in a house with a wood stove as the only source of heat, and my parents would occasionally use some coal in it. Dad also had a coal forge for hobby blacksmithing.