I've got a motion alarm on my bicycle, which is in the same vein I suppose. If my bike gets jostled it'll first do quite a stern beeping. If it keeps getting mo

I've got a motion alarm on my bicycle, which is in the same vein I suppose. If my bike gets jostled it'll first do quite a stern beeping. If it keeps getting moved after some seconds it will produce a LOUD alarm. If nothing else it'll annoy any potential bike thieves. Of course any thief with an angle grinder can easily pop the metal zip ties the alarm is attached with, but then an angle grinder is probably going to be louder than the alarm in any case. My tactic has always been to make my bicycle slightly more annoying to steal than any of the bicycles next to it.