Windows only: If you prefer web-based email like Gmail or Yahoo Mail, Affixa seamlessly bridges the gap between the web and your desktop for painless file attachments, mailto links, and more. Affixa integrates webmail with every corner of your desktop. As you can see in the video, each time you encounter an email situation in Windows, Affixa lets you choose what email account you'd like to use—meaning that you can easily switch between sending an attachment via Outlook for work or your personal Gmail account, for example. Affixa will handle attachments you send to your email from the right-click menu or directly through any applications (like Word's Email option). If your email client has limits on attachment size or file-type, Affixa can upload the attachment to previously mentioned file-sharing webapp Drop.io.
Affixa also allows you to create "baskets" into which you can drag and drop any files, zip them up, and email them quickly and easily. The application is actually an improved version of previously mentioned gAttach and yAttach, which brought much of the same functionality to Gmail and Yahoo mail accounts individually. If you use Gmail as your main email account, I can't think of a good reason why you wouldn't want to use Affixa. Affixa is a free download for personal use, Windows only. If you want the full, unlimited functionality, you can upgrade to Affixa's subscription version for rougly $3.