Currently this application is only available for use in a Windows or *nix environment.
said by GML Homepage:The application works by reading your existing mail files, and forwarding them to GMail. It does not delete the mail from your local computer. Email can be set to arrive at GMail in either your 'Inbox' or 'Sent Mail'.
GML is free and is licensed to you under the GNU General Public License. There is a pre-compiled windows version avaiable as well as a source only distribution for other operating systems. Please see the download page for more information.
Here's a comprehensive list of some free GMail tools and plugins:
•Gmail Notifier The Gmail Notifier is a downloadable Windows application that alerts you when you have new Gmail messages. It displays an icon in your system tray to let you know if you have unread Gmail messages, and shows you their subjects, senders and snippets, all without your having to open a web browser.
•GMNotifier GMNotifier is a notifier application that tells you when you have new Gmail messages.
•GmailTray GmailTray allows you to search your emails from your desktop. It resides in your system tray, and can be accessed by simply clicking on it. This will bring up a box that you can enter your search in. To start the search, hit enter. It will then search using your default browser.
•Gmail Notifier Firefox extension, installs an icon on your toolbar that displays the amount of new messages in your inbox
•Gmail-to Associate all mailto: links with Gmail as opposed to Outlook