Farm Jack, Off Road Jack, Wagon Jack, (The Kleenex name is Hi-Lift Jack).
Lots of people make them with the most famous being Hi-Lift, the most common probably being Harbor Freight, and the crappiest probably being Reese. Most of us know what they are, and those of us who have one (or more) have probably used them for some pretty sketchy stuff.
I was using one yesterday to lift up a big heavy steel work bench to slide a furniture dolly under two of the legs, and I thought it would sure be handy if somebody welded a hook or a ring on the two cross pins to make it easier to pull out the pin that should click out on its own but doesn't because the jack is dirty, stained, and grungy from the last job and rarely gets maintained. On my last truck I used to keep a can of silicone dry lube in the tool box just to spray down the action of the jack when I needed it.
Now I am sure somebody would get pinched putting their finger near the mechanism, and some real genius would find away to pull the p[in out that's supporting the lad and kill somebody, but it sure would be handy if there was a hook of a ring welded to those two cross pins so I wouldn't have to stop mid job with me keeping the load from falling by pushing with my knee and go find some cleaner and some lube for the jack.