Streams, Voice, and Sensitive Dependence

["Lee Davis"<lee.davis@thomasmore.edu>]

It is my understanding that the PGP algorithm is primarily intended as a block
cypher.  Therefore, wouldn't an Outer Block stream cypher be more effective for
phone conversations?  Both solutions require hardware for a practical (tolerably
noiseless) implementation, so there's nothing to be gained by streaming data
into a block format.

In any case, there has been a lot of recent work in dynamic systems (Chaos),
especially in the fast computations of Julia Sets.  Has anyone seen a paper on
exploiting the sensitive dependance in these systems for pseudorandom number
generation?