Attach Large Files was the Yahoo! Mail integration that I built as a developer for drop.io. It allowed Yahoo! Mail users to seamlessly attach large files (up to 100MB) to their e-mails by using drop.io to host the files and then placing download links and previews of the files into the body of their e-mails. Since they had previously limited their users to 20MB per e-mail, the Yahoo! Mail team was so excited to see the app that it initially became a default install for 20 million US users. The app was later released to another 80 million US and international users.