He doesn't use dropbox. He uses an ftp server I run that you upload your file and it sends a download link to the recipient. It hides the file, you can only get to it from the link. It also automatically deletes the file after 14 days. Has a desktop app you can see if they downloaded it or not. You can also just drop the file on the app and it will upload it with your login. It also has a web interface. Instead of dropbox the feature is called Drop Ship. Provide access as part of hosting an email account with me. Had it long before dropbox ever existed. You can check it out at
zipbang.com
That alien sounds like it almost has the "somebody else's problem" field from the Hitchhiker's Guide Books. Has a space ship that becomes invisible by generating a somebody else's problem field. Nobody can see it because it's somebody else's problem.