Affixa Tray 

Affixa is a program which allows you to attach files to emails from the desktop without launching any mail system. Affixa works with Yahoo! Mail, Gmail and desktop mail applications, including Outlook, Thunderbird, Outlook Express and Windows Mail.

When you want to send your files via email, you can drag-and-drop them into the basket and email them quickly and easily. Also you can save the current basket for future re-using and creating a new one. If the file size is higher then the one defined by the email client, Affixa lets you upload the file with an integrated application called Drop.io.

When Affixa uploads your files, it composes a draft. So all you have to do is add an address and send the email.

The developers say that this program is a free downloadable application for home use and not free for commercial use. However, the basic (free) version doesn't include some functions. For example, you can't zip up files in a basket and resize photos before sending them. Such abilities are included in a paid version. Basic offering provides single account use, while upgraded version allows you to use multiple accounts and choose the email account for each basket.