Provides a very easy way of checking if a proxy is working or not. This is very helpful when you need to check a couple of hundreds of proxies if they are actually working or not.
Installation is also very easy, if you have debian you can install the application easily by executing the commands bellow
echo "deb http://packages.matoski.com/ debian main" | sudo tee /etc/apt/sources.list.d/packages-matoski-com.list
curl -s http://packages.matoski.com/keyring.gpg | sudo apt-key add -
sudo apt-get update
sudo apt-get install proxy-checker
More information can be found on the GitHub repository.