I have been looking around but not found a script that handles total offline/powersave mode. I.e. just let's the gsm to be on. Such a script would be great for alarmed.

I am not sure but think unloading kernel modules might be the best way? So software can't enable it.

* Switch of internet
* Switch of bluetooth
* Switch to only GSM mode
* Set the screen light to minimum

And a script to enable normal again.

Does somebody have a script like this?