Personal information management (PIM) is a key component of mobile devices and for years I used iambic Agendus on my Palm OS devices since it offered a consolidated way to manage my calendar, contacts, and tasks. I also use software like this now on my Windows Mobile devices and have tried some on S60 as well. I just read the press release announcing that Agendus for BlackBerry is now available for US$19.95 and also works with the desktop component.
I keep going back to my BlackBerry Curve on T-Mobile and it will be tough to give it up next month when the G1 is launched. Agendus for BlackBerry integrates your Calendar, Contacts, and Tasks in a seamless manner. The same data storage location is used with the native PIM clients so there is no repeat of data and Agendus makes the presentation and ability to work together better. You also can get weather forecasts, quote of the day and This Day in History facts through your wireless connection. Agendus adjusts for your selected theme too and is compatible with the Bold and Flip. I plan to go try it on my Curve now.