Drush

Drush can be one of the nicest tools to have, when you want to speed up quite a lot of your daily Drupal operations.

Here are some of the usages I've come across, for Drupal 7:

Clearing cache:

# clear all caches
drush cc all

# rebuild caches
drush cr

Download and enable modules:

# download module modulename
drush dl modulename

# enable a downloaded module
drush en modulename

# to skip the Yes or No confirmation questions:
drush -y en modulename

With SSH enabled, Drush is one of the best command-line tools that a Drupal developer/admin can have.

If you havent heard of Drush, checkout these pages to know more about it, and about how it can help make your life much saner:
https://github.com/drush-ops/drush#description
http://drush.ws/about

Here is how you can install Drush on your cPanel/WHM shared hosting account: