LiveCycle ES Preview
I've been working on integrating the Form Designer product I work on with the Eclipse-based Workbench that's the new integrating piece of LiveCycle, and now there's a preview release available on Adobe.com:
http://www.adobe.com/devnet/livecycle/espreview/
Run the setup for the server and you get a working server capable of some pretty cool stuff with forms, workflow, and PDF. Run the client setup and you get the Workbench installed with the workflow design tool and the Form Designer tool that I work on.
It's not something you're likely going to want at home, but for any sort of form workflow or intelligent document generation, it's powerful stuff.