There are all kinds of offline filesharing possibilities. I learn about more of them every day now :-) Check out deadSwap. Thx Dmytri!
deadSwap: A Game Of Cloak And Data
deadSwap is an offline file sharing system where participants covertly pass a USB stick from one to another. The route of the USB memory stick and the identity of the other participants is not known by the users but controlled by local, independently operated SMS gateways that are kept as a carefully shared secret by their users.
deadSwap is a social experiment exploring the possibilities of creating an entirely off-line file-sharing and communications platform where people pass a USB memory stick from one to another.
The coordination of the passing-on of the stick is done through an anonymous SMS gateway, meaning that the system does not require Internet availability and also that, with certain precautions, it can be a very private system that is quite difficult to monitor.