Kitchen Gas Leakage Alarm
This is a very simple weekend project: A gas leakage alarm for your kitchen.
It's based on a MQ-2 sensor, which detects LGP (Liquefied Petroleum Gas), alcohol, smoke, propane and some other gases. It comes froma family of sensors, all of them with the same pinout, so any project using them can be easily "ported" to detect different gases. For example, MQ-7 detects Carbon Monoxide and ME2-O2 detects Oxigen.