Using the power of SMS, Phone Guardian 1.0 promises to help recover your Symbian Series 60 3rd Edition phone. A thief won't be able to use your mobile once it receives a secret Lock SMS (presumably sent by you). And when the crook swaps SIMs, the smartphone-in-distress will send a text to a pre-defined number, possibly revealing its own location. A loud siren can even be set to play when the mobile enters lock mode.

Of course, all the locks can be undone by entering the proper codes. If you're interested, head over to Symbian Guru. They have a 5-day trial version available, along with the user manual.