One of the things that normal document management systems do, and that some of the online content management systems also support, is uploading binary files so that geographically distributed workgroups can share files that are frequently in binary format. FTP servers are a nuisance to maintain, and proprietary systems that support this are generally expensive. An affordable alternative would be useful.

Of course, there would have to be limits on the amount of space used, or people would load it up with hard-drive backups that they would never even bother to delete. So the space requirements in QDL would have to apply. Registered users only get 1 MB of space for free. Advanced users get 10 MB, and Professional users get 100 MB. More space could be offered, for more money.

There are cheaper ways of hosting files, so people will complain that QDL is charging too much money for disk space. But QDL is more than just a file hosting service — somebody has to pay for all of this additional functionality that QDL has. :)