Mini motion detector guards your goods
Theft of items such as purses and laptops doesn't only happen when they're left unattended for long periods of time – frequently, it occurs when you've just turned your back on them for a minute or two. It was with this in mind that Stilla Motion was created. It's a "coin-sized" motion detector that can be placed on any object, and that will alert you if that object is subsequently moved.
You activate Stilla simply by squeezing it, or via an accompanying iOS/Android app. It can just be laid on a given item, or stuck to it using some included double-sided tape. Once armed, it's able to differentiate between recurring background motion (such as the swaying of a train car), and the sort of movements that would be involved in its getting picked up.
Depending on the settings selected on the app, you will be alerted either via Stilla's own 85-decibel alarm, an alarm tone on your smartphone (the device has a range of 150 ft/46 m), or a combination of both. If you're using phone-alarm-only mode, and the object that was being guarded is no longer in sight by the time you turn around, you can use the app to remotely sound Stilla's onboard alarm.
Additionally, should you simply forget about your purse, laptop, etc and try walking away without it, you'll be alerted as you move out of range.
Stilla Motion is currently the subject of a crowdfunding campaign on Indiegogo, where a pledge of US$29 will get you one, when and if they're ready to go. The planned retail price is approximately $49.