Anyone know of a good free patch creator?

Question

Does anyone know of a good patching program that is free? You know, one that can take a directory with your old program in it and compare it to a directory with your new version, and spit out a patch that is only the difference between the two?

Also, I am looking for something that can patch the entire directory, not just one exe.

EDIT: Thanks for the answers, but I am looking for an end user patch for product updates. Nothing to do with the source.

Answer 1

There is Binary patch and diff, which is free, Windows port available.

Answer 2

I've never used this but it is free. It might be worth a try:

Patch Maker 1.2.