Generally, MobileMe is the easiest way to keep all of your Mac data synched up. Occasionally though, you’ve got an application that you really don’t want the same configuration for in two places. Scouring the SyncServices Developer Documentation, I was finally able to figure out a way to do exclude specific configuration files. Simply execute:

defaults write plist.to.ignore com.apple.PreferenceSync.ExcludeAllSyncKeys -bool YES

Where plist.to.ignore is the plist file name without after truncating the trailing “.plist”. For example, there’s an application called Zooom/2 I use to effortlessly move and resize windows. When using it on a MacBook, I prefer to base activation on the “fn” key located on the lower left of the keyboard, but on an iMac this key isn’t convenient so I should use a different shortcut. Rather than having to give up all of my mobileme preference syncing, or having to deal with desktop style settings on my MacBook, I just close the application and run:

defaults write com.coderage.Zooom2Settings com.apple.PreferenceSync.ExcludeAllSyncKeys -bool YES

Note that there’s also an “com.apple.PreferenceSync.ExcludeSyncKeys” array that you can add to the plist file to exclude an array of specifically named keys from the mobileme sync. For full details see the Apple Developer Connection Sync Services Programming Guide.