The MeteoBox (MeteoKutija) is a cheap device that collects a set of meteorological data and publishes it to a central database. We will use cheap of-the-shelf hardware, such as sensors, micro-controllers and embedded linux devices so that the device would be available to anyone with the will and some patience.
The device is based on a OpenWrt compatible embedded linux device (typically a common WiFi router), and a single AVR micro-controller (attiny2313 or atmega328) for communication with the sensors.
The router needs to have a USART port (easily hacked on TP-Link routers) to communicate with the AVR micro-controller. We will use the CmdMessenger protocol for this communication.
The AVR micro-controller will then communicate with the sensors, either through I²C or 1-Wire protocols. For sensors that don't implement I²C or 1-Wire we'll use a Attiny25 controller to handle the communication.
Once data is gathered on the router it's published to a central database (CouchDB + spatial). Since the database will be open to the public, anyone could make web apps to display the data in a interesting way.