Two things that I
always reach for Emacs to accomplish are git and file management, via Magit and Dired(X) respectively. Here's a quick cheat sheet of the things I use Dired for:
C-x C-j (jump to directory)
Open the current directory in Dired (requires that
you first (require 'dired-x)) from any buffer, even
other directories, but usually from within files.
C-x C-q (edit directory)
Start editing the current directory as a plain-text
buffer and commit changes with C-c C-c or discard
all changes with C-c C-k.
One thing you can do with this is quickly swap two
filenames. Dired will give one of them a temp name
which is super convenient.
Combined with multiple-cursors package, this also
lets you mass rename files in ways that would be
much harder in terminal.
d (delete)
Mark items in directory for deletion, (x) to commit.
m (mark)
Mark items in a directory for:
R - rename (or move)
C - copy
For a more thorough list, open a directory and type C-h m