OS X :: Keeping Macs And Devices In Sync

My purpose is to summarize what I can collect as information on the best way to keep macs and devices in sync.

First, I will focus on the main goal I want to achieve: keep iCal and Address Book in sync for a macbook and a mac mini. The sync can occur via internet (nice-to-have) or simply when they are on the same network (minimum requirement).

Later below are also separately listed info on files/folder sync.

The option I have found so far:

For Address Book and iCal:

1) Mac OS X native option
Mac OS X Snow Leopard offers the possibility to keep iCal and Address Book in sync, via a Google Account or a Yahoo Account.

FREE requires Google account also keep Google Contacts and Calendar in sync But no contacts picture sync, limited phone number (3 or 4 per contact)

2) Mobile Me
iCal, Address Book, ...
+ storage, web hosting, complete integration with Mac OS X...
79$ / year

3) Others...

Spanning Sync 3
http://spanningsync.com/
Almost as option 1) as it requires a Google Account.

BusySync

Fruux
[url]
Only between computers. But they don't need to be ON at the same time (using fruux cloud).
FREE
BETA
also sync bookmarks and notes.
10.5 and upper.

For files/folder sync:

1) Mobile Me iDisk

2) Dropbox and analog, whether they are webbased on full applications
Dropbox
[url]
Chronosync
Amazon S3
Microsoft Live Mesh
[url]
[url]
[url]
[url]

3) Other solutions, more manual...
[url]
rSync
Part of OS X already. You may need to update it depending on the task, but if you can figure it out, here it is:
rSync

What am I using? I am now trying Fruux. Free and doing exactly what I needed: sync 2 macs for address book and calendar. Not less, and a little more. More after a few days of use!