1. Download and install Google Talk by visiting http://www.google.com/talk/
2. Log in using your full Brown email address as your username:
3. Once you are logged in, click Settings on the top right and check the "Open Gmail when I click on email links" checkbox:
Google Talk will start automatically when you turn on your computer. It also provides new email notifications on the bottom right of your screen. If you would like to disable these notifications, you can do so in the settings.