Hi,
I've had lots of fun with my Z, but I'm still not using it for what I originally bought it for - a PDA.
Although I've installed the Ki PIM tools, I'm still using the default Sharp ones as they're much faster.
In any case, the reason why I'm not really using it as a PDA is that I haven't found a sync solution that I like. I use iCal on my mac, and was using Qtopia Desktop on my PC but I never got it to sync properly with newer Cacko's.
I'm not sure what solution exactly I want. I developed a web-based PIM tool some time ago that I might start using if I can get it to sync with my Z, but it'll mean the Z needs to talk some standard format and be able to understand updated entries, etc.
For now, I'd be happy with it syncing over my 802.11b wireless card, my todo's/calendar, to preferably iCal on OS X, but any decent application on Windows/Linux.
What applications/sync methods are people using to achieve this? Do you use your Z as a PDA, or a expensive toy? :-)