The cost of solid state memories is falling dramatically. What about, for some scenarios where the difficulties of key exchange are not prohibitive, reverting to one-time pads?
Couldn’t be done with ordinary filesystems where wear balancing would leave copies of the key material all over the disk. With a serial flash chip it however could work - any memory where a certain block you write to will be still the same block, and therefore if you erase it the data on it will be gone without leaving around copies, would do the job - the key has to be destroyed immediately after use.
Perfect forward secrecy, simple transparent algorithm, with good key generation system it is virtually unbreakable by means other than side channels.
