Ever thought “I need a lot of minerals moved. I wonder what quantities of (compressed) ore I need to supply that?”
Turns out there’s a neat compression calculator for that. It only cares about low- and mid-end minerals, which is fair enough.
Fuzzworks also has one that allows you to enter your skills should you not have perfect refining, but is less informative about the results it gives.
Serpentine's Eve 