My 7-year-old MacBook got bricked. So I needed to recover some MySQL files from a Time Machine backup and load them onto a new computer. And so I've been digging around finding out where all my homebrew and MySQL files are. While running mulitple instances of everything! Here's a fairly unstructured brain-dump of all that I've learned (or re-learned) along the way.
A bunch of @climagic's command-line keyboard shortcuts collated for reference.