MD5 Comparison snapshot of current Magento release files. Works and tested on OSX, CentOS; though OSX requires md5 instead of md5sum

compare-core-mods.sh

#!/bin/bash

find app/code/core/Mage app/code/core/Enterprise app/code/core/Zend lib/Varien lib/Mage lib/Zend  -type f | grep -v '\.svn' | sort -d -f -k1 | xargs md5sum | awk {'print $2, $1'} > 1.11.2.0.local.md5

diff 1.11.2.0.base.md5 1.11.2.0.local.md5

generate-checksum-doc.sh

#!/bin/bash
#against a clean repo checkout (should ignore svn dirs)

find app/code/core/Mage app/code/core/Enterprise app/code/core/Zend lib/Varien lib/Mage lib/Zend  -type f | grep -v '\.svn' | sort -d -f -k1 | xargs md5sum | awk {'print $2, $1'} > 1.11.2.0.base.md5

sample-md5-checksum-doc.txt

#1.11.2.0-EE

app/code/core/Enterprise/AdminGws/Block/Adminhtml/Permissions/Grid/Renderer/Gws.php 903a3b5a3e24ed4eace7236b58e52815
app/code/core/Enterprise/AdminGws/Block/Adminhtml/Permissions/Grid/Role.php 3d4d96f2940af00888cd3d0f3bcbb3ae
app/code/core/Enterprise/AdminGws/Block/Adminhtml/Permissions/Tab/Rolesedit/Gws.php 4184c4a0043ac9e76958e3426ba8a8b6
app/code/core/Enterprise/AdminGws/Controller/Exception.php 31af4527690f91e37af59237d3d1fb20
app/code/core/Enterprise/AdminGws/etc/config.xml a1d16acfc3143bbbb4cb91bf3865041a
app/code/core/Enterprise/AdminGws/Helper/Data.php f18a904b17971104efb690fa89411e2a
...

Run the generate doc first against a clean checkout. It should output a doc like 1.11.2.0.base.md5 -- you can then run the compare-core-mods.sh file. Feel free to rename the file to your actual version.

Let me know if you'd like me to publish the md5 docs for the following versions which I already have: 1.10.1.1, 1.11.2.0, 1.12.0.2 -- I'd like to do some major CE releases as well.

This is excellent. We as a community should definitely maintain and publish hashes.