Interesting fact about painkillers. The work better if you actually take them. Having lay in bed waiting for the painkillers to kick in and nothing happening, I wanderes back to my desk to find them sat there next to my drink...
I'm now the proud owner of a set of gauge blocks. These are one of the most precise things I own (microchips and camera lenses hold that title). Each is ground to ±300nM. The surface is so smooth they they can be wrung together and become incredibly hard to pull apart. These will become the origin for all precision in my machining.
Do I need anything this precise? Nope.
Am I very happy with my shiny new toy? Hellyes.