An Arduino is equipped with a piezo sensor to detect impact, and a GSM shield takes care of the texting. It’s an interesting concept, similar to requiring police officers to wear body cameras.

Real Time Home Security System using GSM Technology-An Anti-theft System! This project deals with the design & development of a theft control system for home, which is being used to prevent/control ...

If you've mastered the art of Arduino, but haven't yet been brave enough to toss in a bit of GSM communication, the how-to guides linked below definitely deserve your attention.