How do I sync an iCal calendar across Lion, Lepoard, and iOS 5? My Dad wants to be able to sync his iCal calendar across a Lion MBP, a Leopard MB, and an iPad running iOS 5. Since the Leopard MB doesn't support iCloud, I can't use that. How can I sync an iCal calendar across all these devices?

I've tried to use Google Calendar, but with no success. Maybe it's the way I'm importing it, but I can't get the colors to show up correctly in iCal. When I link iCal to Google Calendar, I want the calendars to look the same in the sidebar. It is a bit confusing with out a screenshot, but I will post a screenshot as soon as I have my Dad's laptop.
I suggest you use Google Calendar (CalDav). You can import these into iCal (both on iPad and Mac). It sync automatically too, so you can have all iCloud-benefits.

I use it with my girlfriend (who is, sadly enough a windows user) and with my company PC. It works like a charm!