Yesterday I posted twenty reasons to do code reviews, and I promised a list of code review tools. Here they are, in no particular order. I have not used all of them, so I can't comment on their relative merits. If there are some I missed, please leave a comment and I'll update this list.

• Codestriker Open source, web based, written in perl I think.
• Code Collaborator Commercial.
• Review Board Open source, web based, appears to be python/Django.
• Rietveld Open source from Google. Guido van Rossum's 2nd pass at a code review tool. You get three guesses on the implementation language...
• Crucible Commercial from Atlassian.

Bottom line: don't try to do this by hand, you'll be wasting a bunch of time packaging patches and tracking defects when a tool can do it automagically for you.