In the distant past, the Address Book app in Mac OS X Tiger could send mobile SMS messages directly from within the app, if you paired your mobile phone with your Mac via Bluetooth. Along came Leopard, and the feature mysteriously vanished without trace or explanation, and hasn’t reappeared since. Missing the feature, I found a roundabout replacement in the emitSMS dashboard widget. It offers SMS sending via Bluetooth and can also search the Address Book for phone numbers. Having seen that the source code for emitSMS was released, I adapted the backend into a plugin for Address Book.app to provide the missing former functionality.