The first major addition to HandyNotes I would love to see is a pure-Java version that can run on any platform. The good news is that the core of HandyNotes, including note parsing, synchronization, and a few other things, is already written in pure Java. The GUI, on the other hand, uses the proprietary Microsoft WFC (Windows Foundation Classes), which give it the Windows "native application" look and give it access to the Win32 API. So the job would basically be implementing a HandyNotes GUI using Swing.

The other thing is that HandyNotes will have is a plugin architecture, so anyone can easily write plugins for it that users can download and install. Examples of possible plugins are a PalmPilot synchronization module, an Outlook Notes synchronization module, and so on.

I will post details soon on how to become a HandyNotes developer soon. Meanwhile, you can look at the source code that's packaged in the download file. It's not very commented yet so I will try to release a more annotated version sometime soon. Meanwhile, I suggest you subscribe to the developer mailing list!