Discovered this little bit of useful info today, to hide your mobile phone number when you call someone (using a Blackberry), select the green Call button, then press the main scroll button (the one you use to move around the screen with), then scroll down the menu to “OPTIONS”, select it and select “General Options”, scroll down to “Restrict My Identity” (don’t be confused with “OPTIONS” on the main Blackberry screen, you must be in the Call menu where all your contacts appear that you have called or received a call from).

Change the setting here to the setting required.

Please note, if you call me and there is no number showing I wont answer 🙂