Almost new VHF radios come with DSC. Why not have a black box that connects your GPS to DSC so that in the event that your boat drags anchor the black box is triggered to send a DSC tone to your handheld while you're away from the boat. We always carry the handheld ashore with us. Quite often going to shore soon after anchoring in a new or iffy area. If the wind come up we can get a bit paranoid wondering if the boat is secure or dragging. This way we would be warned.

Hell, you could extend that to include sending a tone via DSC if the companionway door is slid meaning someone has entered the boat while you're away. Or a water alarm.

Once it's set up you could even put your handheld next to the bed at night and it could notify you of a number of things while you're sleeping.

Should be easy to design,,, Someone do it!