This program can be pretty useful because it provides you the possibility to attach files to your messages. It reassigns Gmail to be the default mail account from Windows documents. The only thing you have to do is to install the program, then you will select Send from Windows Explorer, Firefox and Microsoft Office and it automatically attaches the files to a Gmail composition instead of Outlook mail. You can also send mails directly from Adobe Acrobat, Windows Live Photo Gallery, Mozilla Firefox and you will see how useful can be to automatically do it and not manually uploading each file. Software's free and working for Windows.
This software is no longer available. gAttach is now Affixa.