birdnest is a Twitter API proxy which filter out the unnecessary information off the Twitter response. This result better utilization of bandwidth for Twitter mobile client, primarily for jibjib.
A semi-automated, largely passive web application security audit tool, optimized for an accurate and sensitive detection, and automatic annotation, of potential problems and security-relevant design patterns based on the observation of existing, user-initiated traffic in complex web 2.0 environments.
memcached + integrated proxy + more
A rendezvous proxy broadcaster allowing advertising of services for other machines that do not support multicasting their configuration information.
nginx [engine x] is a HTTP server and mail proxy server
Burp proxy is an interactive HTTP/S proxy server for attacking and debugging web-enabled applications.