Want to see where all your disk space has gone? Of course, on *nix systems there is du, but there are nicer ways to get an overview of disk usage. One is ncdu which is du with an ncurses interface (plus some features). Meaning, one can browse the du results interactively in the terminal.

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For Mac, install via brew install ncdu. Great tool for personal use and on remote servers, should run in every POSIX environment with ncurses installed!