I stay in Bangalore and houses here do not have central heating / cooling - the weather is not extreme and generally a small room heater to heat the room during winters is sufficient. However, the heater needs to be switched off as it becomes too hot and uncomfortable.
Also, the weather gets kind of dry and I use a small steamer as a humidifier.

I recently got into microcontroller programming, and the first project I thought of was to set an automatic room heating cum humidifier system.

Continuing from Standalone Arduino (http://dushyant.ahuja.ws/2013/10/standalone-arduino/), created a standalone thermometer and humidity control.

More details at:
http://dushyant.ahuja.ws/2013/11/standalone-temperature-and-humidity-control/