Five Arduino-Based Remote Monitoring Projects
As you are probably aware, Arduino is an open source hardware/software combination. The hardware is built using a great variety of components, inputs, outputs and sensors. The software is usually built using the C or C++ programming languages.

Here are some of the most interesting remote monitoring projects that were built using Arduino.
a) Smart Health Kit

This ambitious E-health system helps patients communicate better and faster with their doctors. And if there is an emergency, the patient will be automatically connected to the closest hospital in the area.

Here's an image that shows how the system works.

A dedicated pulse sensor, a temperature sensor, a GPS and a small display provide all the needed information.
b) Aquarium Controller and Monitor

ET fishbowl is a small device that is able to feed your fish at the specified hours.

It also has the ability of controlling the amount of light, water level, oxygen level, and more.
c) Plant Assistant

This project helps you determine if your plants are doing OK. Find out if they have enough water and sunlight, even when you aren't at home. You can also check the air quality using a dedicated sensor.

The system includes water and fertilizer tanks, along with a soil moisture meter. An inexpensive TPH sensor provides the needed data, helping determine the air temperature and humidity.
d) Remote Door Opening Monitor

If you aren't at home that much, you will love this project! It uses a magnetic sensor to trigger the door detection signal. And when this happens, the system will send you an email using Google Gmail.

This is a very simple project from a hardware point of view; the hard part is done by PHPoC Shield, which helps Arduino connect to the Internet either through a wired, or a wireless network.
e) DogWatcher

If you are a cat person, read the following words at your own risk: dogs are SO much better companions! Well, I guess that DogWatcher may work fine for cats, too...

This adorable project will try to keep your lovely dog away from areas that aren't his/her business by sounding an alarm whenever he/she comes close. And do you know that innocent look that Spot is able to display the minute after he has finished chewing your shoes? Well, now you've got the proof, because DogWatcher is able to take pictures as well.
The project utilizes the Windows Remote Arduino library, which makes it really easy to see what your dog is up to, even if you aren't at home.