Congrats on the project. Without loading and looking myself, how are the file accessible on the server? I asked because I'd like to have clients use this to send ME files only. Is that an option?
Currently, the files are stored as a flat file list on the file system using their randomly generated token to create a [token].json and [token].binary file. The JSON file contains meta information, the .binary file is the actual file.
Using the default settings, you would get something like "./uploads/0b692a00635682fabc78b6a50655242c.binary" in the application directory.
I've already has plans on making it possible to change the interface, for instance not allowing direct download from the homepage. I could ament this with the feature to send email notifications to the system administrator upon successful file transfer. The combination of both would allow you to use YouTransfer.io as a public drop box for files. Does this sound about right to you?