- Notify you when the mail arrives
- Track your dog’s poop and bark locations
- Monitor for people in different parts of the house
- Check for water leaks
- Alert you when the dog runs away
- Not only check when the washer or dryer is finished, but also if someone has been there already
- Watch the temperature and humidity in different rooms
- etc. etc.
using a Raspberry Pi, a few Arduino clones, some cheap sensors from eBay, and openHAB as the brains of the operation.
Head over to Instructables instructions and get started with a cheap but very advanced home automation system.