Combining If This Then That with OS X's Automator means you can notify yourself whenever something important happens on your Mac.
With the help of Automator you can create a reminder on your Mac without ever launching the Reminders app.
With a new year comes a looming tax date and the need to create records of where and how you spent and made money. Automator can help compile records of your whereabouts.
You've created hundreds of files using one naming convention only to discover that a different convention is required. Don't sweat it. With Automator you can batch rename them with ease.
Care to check in on the area in front of your computer while you're away from home? With Automator and a properly configured Mac, you can.