I implemented this at Go Daddy for our internal KB around 2006/7 after someone started leaking docs. It was pretty reliable, but had some interesting failure mo

I implemented this at Go Daddy for our internal KB around 2006/7 after someone started leaking docs. It was pretty reliable, but had some interesting failure modes: not being able to search for words with transposed glyphs, excluding code listings and other things that might be copy/pasted.