de`code;

Instructions for ubuntu only. (specifically ubuntu 12.04 LTS , but should work on 10.04 +)

1. sudo apt-get install git (ignore if git already installed)
2. cd /tmp
3. git clone -b auth git://github.com/meteor/meteor.git
4. cd meteor
5. sudo ./install.sh

You are done!
Go to any directory, create a meteor app.

Example :

1.  cd /home/USERNAME
2. meteor create my_auth_app
3. meteor add accounts-ui
4. meteor add accounts-google accounts-facebook accounts-password
5. meteor

Your app is now auth enabled, with facebook and google login and username/password registration/login.

More instructions at  https://github.com/meteor/meteor/wiki/Getting-Started-with-Auth