I feel like you're all forgetting the trusty old flat head screw driver. The single most useless screwdriver and yet somehow most useful tool at the same time. Is there a job where you don't need to poke, prod or pry at something?
A few weeks ago, I used a flat head screwdriver to tighten and replace some screws in an old piece of furniture.
It felt kinda weird to abuse my pry bars that way.
Mostly Japanese brand motorcycle work here, and our cars are Toy Yodas.
1) Light. I have an assortment, but the most-used is one of those Harbor Freight rechargeable folding stick dealios. I have two of these, actually.
2) Harbor Freight 1/4" drive roto ratchet with a 10mm deep socket. I never even bother to put the socket back on the rail. I have at least four of these 1/4" drive roto rats around. They're insanely useful. Usually one gets an 8mm and another gets a 12mm for the duration of whatever I'm doing, but the 10mm pretty much remains permanently mounted.
3) If you count my air compressor and motorcycle lift table as "shop equipment" and not tools, then third place might go to one of several pairs of Hakko flush cutters. I seem to need these for cutting a wire or cable tie several times for each project. I keep several pairs around so they're always handy. I also consider them a consumable; eventually the edges deteriorate so they won't cut cleanly, so I have to say goodbye. A box of five pairs on Amazon is quite cheap for the quality you get.
