How to program for the phone's main screen

Hey everyone,
Anyone know how to program for the main screen?

1) Either through the Active Standby screen: have the active standby show appointments from my written app and not Nokia's calendar

2) Without Active Standby - just start drawing whatever on the main screen.  For instance, drawing the appointments from the Nokia Calendar to show up on the screen but with added functionality.  Writing an app that will "sit" on the main screen, instead of having to open it through shortcut or the menu.


BTW, you guys rule! (your knowledge is unchallenged)