We are working on a scheme for charging for delivery of data with the indra project https://github.com/indra-lab/indra

It provides the delivery guarantee side, provides a service advertisment for delivery of such service. A micropaywall to access a file repository on a bytes of data basis would be very easy to construct, indra forms the first leg that enables forward anonymity, and the user provides the return path, protecting their location from the hosting service.

We are putting the finishing touches on the hidden service protocol also, which would enable such file hosting to be anonymous both for the client side and server side. Currently there is no accounting enabled for hidden services to charge for read/write access, but this will be necessary to complete the protocol.

Indra is being designed from the ground up to be extremely unopinionated and flexible. If you can think of ways in which charging for forwarding data from one point to another can be part of a service protocol it can give you the monetisation side to make it profitable/break even.