Arduino + SENSORS(Moisture, LM35, HC-SR04 Ultrasonic distance sensor)

1. You will get to know Arduino ino files here to solve some of environmental & civic issues.
2. Finding the total capacity of any tank(water overhead,cylinder, gas etc) or Height of a person too :-P
3. Know the moisture in soil and water plants.Can be used to segreagte waste according to Wet or Dry also.
4. Know the temperature and automatically switch of devices using LM35(Cordior light controller in my appartments) And many more real time solutions which solves environmental and civic issues easily.