Why is there only non-free software in this? GNOME is free software, we promote, we dream and we advocate free software. This’d not be on by default, please?

I’ve been looking for a while now, and can’t find it. I’m using a Mac in the office, and would like to use Linux at home. However, I’m stuck with all my appointments in iCal and mail in Mail. I can basically never decently boot into Linux because I will miss appointments. I need something that can interoperate with iCal and use the _same_ calender under both OSes (I sppose IMAP could do mail). Web-interfaces are not acceptable, I want to use iCal under the Mac and Evolution under Linux.

Does anything like that exist? I basically want Outlook and Exchange without Outlook (and probably without Exchange ). Can GMail do that, for example? Bonus points if it can import an existing calender from iCal.