What's the smallest (battery) device that works with Vera?

Hi

As part of my attempt to build my first plugin (a Proximity Sensor) I’m trying to find the smallest, most portable (hence battery powered) device that works with Vera?

Please note, It does not have to be z-wave, it could also be anything. e.g something that works on 433mhz with e.g the RFXrtx plugin etc.

Any thoughts?

This Fibaro device is pretty cute and small: http://www.hashop.nl/Webwinkel-Product-14968292/Z-Wave-Universal-Binary-Sensor.html. Only drawback is that it does require 9v, so you can’t run it off 2-3 AA cells like some other devices.

Your other option is to get a door sensor. They are small, and trivial to hack in order to react to any other event that can open/close a contact.