Automated functional testing is one of the most valuable tools your organization can implement. You get the benefit of having repeatable, fast running tests that do not require expensive humans to run them and are less error prone. I'm a big fan of anything that can be done for me while I'm sleeping.
Here are the slides for an upcoming talk I am giving on automating tests using Selenium IDE. This presentation contains a brief overview of automated testing, why you should consider automation, and how to get Selenium IDE up and running.