The [amazing] music site Last.fm has an events calendar system. Each artist page has an events listing, showing you when they’re playing where. There’s a great social networking mechanism where you can say that you plan to attend an event. You can see other users who are going, and there’s a message board for posting notes about the event. There’s even a unique Flickr tag for each event, and photos posted with that tag will automatically show up on that event’s page on Last.fm. As a user, you get an events calendar on the Last.fm site, but you’re planned events aren’t stuck there.
At the top of your events page there’s a iCal sync link. Click that link will add a subscription to your iCal that will auto update your calendar with your planned events. This is killer, the exact type of information freedom that we’ve come to expect from cutting edge sites. I recently found that it is possible to export Facebook events into iCal, but it looks like a one-time syncronization, and will have to be repeated as you add new events in Facebook. Last.fm, however, will automatically update your calendar, which makes the whole transaction seamless to the user.
What other sites with “event” tools have this level of syncing?