Automator - Batch files for the 21st century

I just got my hands on a copy of Apple's new Mac OS 10.4 ("Tiger") While the new features like RSS support, integrated searching, and dashboard features have received a lot of attention, a new feature called Automator is a great addition. Automator allows you to create "workflows" of commonly used functions and save them for reuse. It is tremendously easy to create a new workflow using actions from most of the OS X apps by just dragging and dropping.

While it is certainly not a full-purpose programming tool, it has enough functionality to create some great time-savers.