Some of my key tools are inherently corrosion-resistant - Nautitool crescent wrench and vise-grip equivalent, stainless Megapro multi-bit screwdriver, and gold-plated ball drivers. Of course, pricey things sink just as fast as cheap
ones, so I've been known to tether the Nautitool stuff to my wrist when in awkward spots.
As to the rest, I agree about Boe-Shield, and have been trying Corrosion-X here and there. I use vapor-phase corrosion
inhibitors in places that are almost always closed, but have trouble imagining them being too helpful in a tool box.
Speaking of tool boxes, I'm looking at the Grizzly oak ones (H7716
to be precise). I haven't had my hands on one yet and wonder if they are robust enough... anybody have one? The current
system of rolled pouches nestled into a low drawer is way too fiddly, and that translates into tools left lying around most of the time. I'm converting the salon
into a lab, and that size tool box will fit at the end of a row of console enclosures.