gpg "simplified"?

[peter.segment at wronghead.com]

I have been asked to help a small group of individuals
(perhaps hundreds, not thousands) with secure data exchange
(including, but not restricted to e-mail).

Use of full gpg is way beyond their capabilities. I am
wondering if anybody has heard of a simplified version
of gpg; or failing that, I would like to hear any comments
on the feasibility of a collaborative project to create
such a variant, as I am convinced there would have to be
a wider applicability of it.

The following describes the requirements:

1) The program is CLI and operates on (i.e., it encrypts and
decrypts) binary files. It has no connection with any mail
client program or server or mail service and provides
no key management functionality whatsoever.

2) Once encrypted with a (single!) recipients public key, the
file consists of bytes indistinguishable from a random stream.

3) The program can be run from removable media, i.e., it
requires no installation and assumes no network access for
either key exchange or in operation. There are binaries
for all three major platforms (Win32, Linux and Mac OSX).

4) Single key, public or private, resides in a single
file. This file is encrypted with operator's public key
and consists of bytes indistinguishable from a random byte
stream.

5) Public key includes a textual description, but no
unique identification other than the hash of the key.

TIA, Peter M.