I remember writing a script at some point to lock the screensaver in case of high acceleration or if the laptop is tilting by more than a few degrees. The idea

I remember writing a script at some point to lock the screensaver in case of high acceleration or if the laptop is tilting by more than a few degrees. The idea was to lock it if was snatched (or just moved around). However, that would only be effective against a petty thief and not against a forensic team. In that case you'd probable want to additionally flush the filesystems (if you care about data integrity in case of a false positive), overwrite the encryption keys in memory (maybe on disk as well, but then there's no coming back without a backup) and shut down. I wonder if the init scripts prompting for the password, cryptsetup and the LUKS subsystem have been designed to always overwrite copies of the entered password and decrypted keys ASAP.