The Drush Module
The Drush module has recently become one of my favorite new Drupal "toys." Drush, or the Drupal Shell, allows the site admin to do a number of useful things from the command line. Among the most useful is the ability to download and install Drupal modules without ever opening a browser. Just type drush pm install views for instance to install the views module. Even better, type drush pm update and you will be prompted to update any modules that are out of date. (Note: this doesn't yet work for core updates, but it will).
One item that always seemed to be missing, though, was the ability to actually enable the modules that you just downloaded. Enter the Drush Module Manager. This handy tool not only allows you to enable, disable and unintsall modules on the fly, it also automatically solves dependencies, which is really the best part.
I actually thought I was late to the party in discovering these great tools, but I've talked to a lot of developers recently who weren't aware of them, so if you fall into that camp - check them out!