Ok, first an easy one. You already are using pseudo database files for things like memos. Set up a little filesystem emulator that displays entries as files that can be downloaded individually as files, and also, let someone write into the database in the same way. I would very much like to browse my palm via bluetooth and download and upload individual memos, addresses and so on.
Now the more difficult one. Make a true database file system for the palm. Then I could do this kind of thing system wide. I could plug my palm into my mac, have it mount on the desktop and just drag and drop files directly to and from it. I could do this instead of using your miserably slow hotsync app, especially when I just want to add one new memo and don’t want to endure a sync operation. You have one big database to manage, while presenting lots of discreet files to the user. In addition, you can use lots of cool metadata.
I understand database filesystems can be a bitch. But I think it’s worth it. And it should be much simpler implementing this on a palm than say a full sized computer.