Sometimes using Emacs you want to know what variables are being set in the current buffer. C-h v lists all the variables, including buffer-local variables in the minibuffer which you can then search and refine just like any other minibuffer session. This is really handy when you customized some settings using hooks and want to verify they took. For example, setting the org-download directory based on filetags.
See also:
- The Emacs completion stack also helps make everything more discoverable
- Emacs is the ultimate editor building material