might compatibility become a *goal*?

[Skip Montanaro]

    David> Even better and more challenging is something that can refactor
    David> the code on the fly - that most certainly is left as an exercise
    David> for the reader! :-)

Probably not quite what you were thinking of, but:

    http://sourceforge.net/projects/bicyclerepair/

-- 
Skip Montanaro (skip at pobox.com - http://www.mojam.com/)
"Excellant Written and Communications Skills required" - seen on chi.jobs