If you want to keep your contacts and your calendar synchronized between macs, you had the only option to subscribe to mobile me. For me that was not really an option, as I don’t use any of the other services and then $99,- p/a is a bit hefty.
But now there is Fruux, just a single preference pane addition, which keeps all of your addresses (Address Book) and calendars (iCal) and even your safari bookmarks in perfect sync. Best of all, it is in active development and there are some really nice features ahead, like online access to your data and “social sync”, whatever that may be (yes, I’m curious, maybe a replacement for Plaxo?).
Your data is stored at the Fruux servers, securely transported using https (that’s what they claim). You still need to trust the Fruux team with your contacts and calendars.
fruux is a lightweight and convenient system preference pane, that syncs your Address Book, Calendars, Tasks and Bookmarks between different Macs. fruux supports sync conflict resolution which will help you when you changed a record on more than one machine. fruux is currently localized in dutch, english, french, german, italian, spanish and romanian.
Oh, and the app is free (as in beer) and still in beta (all warnings apply, but for me it just works as promised for over a week now). The Dutch localization has one mislabeled button (version 0.9), that’s just a minor issue I found.
Update: I sent the folks at Fruux more details about the Dutch localization issue and they corrected it right away, it will be fixed in the next release!