I don't know if this is even possible. I have to use Windows at work and my calendaring app is Outlook. For my moonlighting startup, we use Backpack from 37 Signals and the calendar on that. At home, I use iCal. This was kind of a pain in the ass before, but now that I have an iPhone, it's killing me not to have these all synched and on the phone. Seems to me that if everything is synched with iCal, everything will be fine.
I don't need to edit the Outlook calendar from anywhere, I just need to pull calendar information from it to iCal. I would like to be able to synch changes made on the iPhone with the various calendars from Backpack and iCal.
Anyone doing this or something like it? How?