Check multiple Gmail inboxes from Terminal.
Replace "emails = ['example@gmail.com', 'example2@gmail.com']" in gist.py with your Gmail addresses. Works for Google Apps accounts too.
Run 'python gist.py'
Type 'login' to authenticate your accounts, 'go' to list unread messages, 'open #' to open the account that has the # index in your web browser, and 'quit' to exit GIST.
Keep your Terminal window open all day for best effect.