Those Calgoo folks are clever. They've included a way to sync more than one calendar with their Hub. They support Outlook and also their own free desktop calendar, named, not surprisingly, Calgoo Calendar.
Here's the cool part. I've already got a Calgoo Hub account. From their desktop calendar, I can browse the calendars in my Hub account and select which ones I want to sync to the desktop.
Why would I want to have the same desktop calendar in two places? Aside from the security that redundancy provides, there's another reason. The new Dell notebook I've just bought isn't powered on all day long. It tends to come out after hours when I'm chatting with River about upcoming events. So I'll have a Calgoo calendar on that notebook. But the other calendar will be on a desktop PC (yes, the same one that was running Sunbird) so if I need to add an event (or look one up) during the work day, I can quickly do that without having to wake up the Dell notebook. I just have to remember to sync to the Hub when I'm prepared to call it a work day.
Yes, I know it's more complicated than just storing one calendar up in the cloud and using Web access. But the way I see it, it's what this whole Microsoft "software+services" thing is all about. So far, it's working for me. (I'm sure that soon Microsoft will have it all figured out as well, if they don't already.)
But Microsoft remains the Windows-only solution. The Calgoo desktop Calendar is available not just for Windows, but for Mac OS X and Linux (Fedora Core 5 and Gentoo distributions) as well. I may have other observations about it after I've used it for a while. Ideally, I would like not to be locked into the Calgoo client, but for now, I'm glad to see it as a free Outlook alternative that does all I've asked of it.
UPDATE: I was able to sync a second set of events to the Hub, so while River still sees only the events she wants to, I can see an additional list of events that I want on my calendar, but since she doesn't subscribe to them, she doesn't see them. Just create a second calendar within Calgoo Calendar, sync it to the Hub, discover it with the second copy of Calgoo Calendar, and sync it from the Hub to that second desktop.