I just want the pi to be able to leverage it's second radio to look for other similarly configured devices in physical proximity, and for it to automatically negotiate an adhoc network between these two devices, exchange files, and terminate the network connection.
Of course, without encryption in transit and signing and verifying the exchanged files, this is dangerous.
I think this could be implemented with PFS for the exchange (autocrypt style) and signing/verifying is on the roadmap.