Ratproxy, Google's site security checker

This is the link to the download & docs.  Some notes from the README:
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There are numerous alternative proxy tools meant to aid security auditors - most notably WebScarab, Paros, Burp, and ProxMon. Stick with whatever suits your needs, as long as you get the data you need in the format you like.

That said, ratproxy is there for a reason. It is designed specifically to deliver concise reports that focus on prioritized issues of clear relevance to contemporary web 2.0 applications, and to do so in a hands-off, repeatable
manner. It should not overwhelm you with raw HTTP traffic dumps, and it goes far beyond simply providing a framework to tamper with the application by hand.
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