Here is another small yet useful Arduino-based project... a device that can be used to measure gas levels in the area and display for easy monitoring. The author has used a simple gas sensor and a small Arduino-compatible board with a 7-segment LED display for output as shown in the following video:
This is the kind of project that illustrates you don't need to use the full-sized Arduino hardware for every project. This would lend itself nicely to the use of our Freetronics LeoStick - perhaps using the onboard piezo to make different sounds depending on the gas level:
However to get started and for more information and the Arduino sketch, visit here.