Here's my "shop" stool!
My shop stool is a semi truck break drum with a 8x8" 3/8" plate welded to the top, to which I welded a length of 1-1/2" black pipe to, then welded a cap and 3/4" nut to, then welded 3/4" allthread to a 12" round 3/8" plate so I can adjust the height of the stool up about 16" above its lowest height of about 48".
Its heavy as hell, but never have to worry about tipping it, and being all steel and having adjustable height, its great for supporting steel when I'm fabricating, since I don't have a welding / fab table.
Not the most comfortable as built, but if I'm using it for longer than a couple a minutes at a time, I just throw a kneeling pad on top and its great!
My primary job is as an electrician, so my primary "work" stool is either an empty 1000' spool of 12-2 NMB or empty spool of MC which is really nice when making up receps during rough in.