Google Email Uploader 

The Google Email Uploader is a great tool for quickly and easily transferring data from a desktop email client to Gmail. It allows you to select messages, attachments, contacts, and other information from a compatible program and quickly establish a transferring line to your profile on the online platform. It also automatically copies all data, ensuring that nothing is lost in the transition. Highly recommended for anyone looking to switch from a desktop email client to Gmail.

Google Email Uploader is a nifty application that helps you backup your mail. The application will install itself and allow you to upload all your e-mails from Desktop-based accounts into Gmail. Of course, that gives you freedom to use the application in many ways. Personally, I used this when I had to migrate all my ISP's e-mail from my Outlook account to Gmail. That process was not going to be easy if carried out manually. If your POP3 server doesn't keep a copy of your messages on the servers, you would have to send each e-mail one at a time to your Gmail account. Gladly, the application took care of everything for me. It even took on the task of saving the dates of the e-mails. Furthermore, it can even save important information as contacts and reminders, for you. The application only works in Windows platforms. It does also require that you use Outlook 2003 or superior, have a Google Apps account and have the Microsoft .NET Framework 2.0. But if you don't have the latter, Google will install it for you.