We almost have that with AntTP right now. It was introduced a few versions ago: AntTP - Serving Autonomi data over HTTP - #313 by Traktion
Certainly, you can upload data and it then passes it to a queued background job. You can upload files instant locally (i.e. from a web page form), then the data flows to the network while you are doing other things.
It won’t really work as a hosted solution just yet, as remote payments are a challenge. I’m waiting on Maidsafe to provide some options on that front, but it should be feasible.
I plan to update IMIM to showcase the changes, but time is always precious.