This includes Dashboard Widgets (complete with onscreen position and settings), Dock items, Keychains (and thus secure passwords for various system and web services), additional email account, email rules and signatures, notes, and all System Preferences settings. All of which pretty much makes it possible to ensure all the Macs that you use always have the same major system and user preferences. Definite value if you routinely use more than one Mac.
MobileMe offers two features for accessing your files and even controlling your Mac remotely. The first is the venerable iDisk, a feature that has been part of MobileMe since its inception in 2000. The iDisk is essentially a virtual hard drive store on Apples servers that delivers 10GB of storage.
Again, this isnt an entirely unique concept Box.net, Microsofts SkyDrive, and others offer similar features but it still is a useful inclusion, especially since it can be easily accessed from any Mac, PC, or an iPhone (using Apples recently introduced free iDisk utility or the commercial OneDisk, which unlike Apples utility allows you to copy files to your iDisk as well as view them).
If simply accessing some of your files isnt enough, MobileMe provides Back To My Mac, a feature that allows you to remotely and securely access your Mac for either file sharing or screen sharing.
While experienced Mac and computer power users can set this feature up without MobileMe, doing so requires configuring your Internet router and requires you to be able to identify your routers IP address (which, with most Internet providers is assigned dynamically and may change).
Back to My Mac allows Apple to leverage the fact that your Mac at home can identify its location and securely authenticate you as a user to make the process easy enough for even a novice to setup.
Ive discussed a lot of the features of MobileMe and whether or not they have free or easy to use equivalents. In many cases, the ease of use has been the overriding advantage. However, there is one feature that is to me the killer reason for any iPhone owner to purchase MobileMe Find My iPhone.
This feature allows you to log into the MobileMe webpage and attempt to locate a lost iPhone. MobileMe sends a message to your iPhone that uses the location services and GPS capabilities of the phone to establish its location and then displays that to you using Google Maps. Thats a huge aid for a lost/stolen phone that likely has a lot of personal data on it.
You can also send a text message to the phone to display to anyone who might find it. And you can issue a command to remotely erase all data on the iPhone quite important for a device with a lot of personal data.
Even if the iPhone isnt turned on, the next time it is activated, it will lock itself and begin the remote wipe. If you later recover the phone, you can restore its contents by syncing it with iTunes.
Find My iPhone can also help youve just lost your phone in your home or office, by playing an alert to help you locate it (something that I used at least once in the first week after the feature was introduced).
Unfortunately when Apple launched the iPhone 3G, a major update to existing iPhones, and MobileMe all at once last summer, there were a number of MobileMe outages (as well as many active delays for new iPhone owners).
In the year since, however, Apple has made a number of improvements to MobileMes backend and even displays the systems status publically. So, while there was a dark cloud of MobileMes initial launch, the service is now largely stable and functional.
In my opinion Mobile Me is a great companion to the iPhone and to Mac OS X. While many of the features are available free or at lower costs from other providers, Apple has delivered several unique features for owners of its products in MobileMe (and has paired it fairly well with the Mac, if not quite so fully featured for Windows).
Apple has made those features easy to use for anyone and almost completely seamless as a service experience across Mac OS X, iLife, the iPhone and iPod touch, Windows, and the web. It may cost a little more, but sometimes you do get what you pay for.