Mac OS X only: Google announced CalDAV support in Google Calendar earlier this year, which meant that with a little know-how, you could sync iCal with Google Calendar. Now the Google Mac Blog has officially announced CalDAV support for iCal, and to go along with the announcement they've released a new iCal sync application called Calaboration. With Calaboration, you can quickly and easily set up bi-directional syncing between iCal and Google Calendar with just a few clicks of your mouse. It's quick, it's easy, and it works like a charm; just run it once to set up your calendar syncing and you shouldn't need to run it again until you need to add a different calendar. Calaboration is a free download, Mac OS X only. If you're not on a Mac, check out how you can sync Google Calendar to any desktop calendar you've got.