This reminds me of an amusing anecdote from PGP's Wikipedia article:
"Zimmermann challenged these regulations in a curious way.
He published the entire source code of PGP in a hardback
book,[12] via MIT Press, which was distributed and sold
widely. Anybody wishing to build their own copy of PGP could
buy the $60 book, cut off the covers, separate the pages, and
scan them using an OCR program, creating a set of source code
text files. One could then build the application using the
freely available GNU Compiler Collection. PGP would thus be
available anywhere in the world. The claimed principle was
simple: export of munitions—guns, bombs, planes, and
software—was (and remains) restricted; but the export of
books is protected by the First Amendment. The question was
never tested in court with respect to PGP. In cases
addressing other encryption software, however, two federal
appeals courts have established the rule that cryptographic
software source code is speech protected by the First
Amendment (the Ninth Circuit Court of Appeals in the
Bernstein case and the Sixth Circuit Court of Appeals in the
Junger case)."
