The Maemo wiki has a page on SMSCON, a python script with some nice ideas for remote control.

SMSCON provides complete control of your N900 by sending SMS commands to it. This is particularly handy in case you cannot find your phone, for example if it has been lost or even stolen.

SMSCON is a two part Python script running in command-line; smscon and smscon_daemon. smscon is the command-line control part and smscon_daemon is the daemon (running in the background) part. The configuration file for all the user settings is in the smscon_config file.

SMSCON will also auto-load silently at boot, waiting for a special SMS command message in case you phone is lost (or even stolen).

SMSCON can’t guarantee that you will find your phone again, but it will provide the maximum chance to recover it. If this application ever helps you to recover your phone please tell the story on Maemo.org! The best way is of course to never lose your phone or let it get stolen…

Recovery of the phone is a start, but obviously remote monitoring and remote control of a linux system using SMS has many other applications in security. One might say this is the future of surveillance systems. Likewise, detecting communication with these devices in your organization has just become even more imperative.