If you really want to become # 1 at UNIX admin job ;) or power user, shell is the key. Mastering shell, shortcuts and various commands result into good speed and improvements in productivity. If you type lots of things everyday this is a must read for you.
There is a nice presentation (slides) and PDF document available at GBdirect website.
=> Tips for driving Bash better in everyday Linux use
=> Command history
=> Searching history
=> Keyboard shortcuts
=> Calling back keywords/commands and command arguments on fly
=> And much more
=> Read online: Power Shell Usage - Bash Tips & Tricks
=> Download PDF version