The single best shell productivity tip for me was to use z:
It automatically makes a list of directories you frequently use in your shell and if you type `z a-small-substring-of-the-directory-path` it does a cd to that directory. (e.g. I type `z and` and it changes my current directory to $HOME/Work/Projects/android`). Saved me tons of typing.
Sound similar to autojump.
https://github.com/wting/autojump