Nuweb
Nuweb is a literate programming tool based on Knuth's web
system (but not related to the World-Wide Web). While Knuth's
original system used a combination of TeX and Pascal, nuweb uses Latex
to control formatting and works with any programming language.
Nuweb was written by Preston Briggs as part of the Massively
Scalar Compiler Project. It is available via
anonymous ftp.