iCal alternative for Windows?

I use OS X to manage most of my life/business. Recently, I find myself in bootcamp more often, learning .NET and C#. I’m using Thunderbird to replace Mail. Is there a suitable free alternative to iCal, where I can subscribe to multiple CalDAV / Google Calendars? I don’t want to have to purchase Office to get Outlook…

Haven’t used it in years, but there’s the Lightning extension for Thunderbird. It worked pretty well back then, so it probably still works now. Personally, I would just use a Prism/Chrome webapp of Google Calendar (and Gmail, for that matter). Desktop mail/calendar software is dead.

Google Calendar should.