blue proxy

RtspProxy is a proxy server for multimedia streaming services.

WebAssistant - Proxy Offline Browser is a neat trick.

BrowseGate3 is a low cost NAT/Proxy/Firewall system

Use a combination mail server and proxy server

psyBNC is a proxy for IRC networks

Terrapin MultiNet is a fully integrated email server and web proxy.

make it easy to write custom firewall/proxy servers

Open-Source Customizable Web Filtering Proxy Server

JNI proxy for calling native code functions and APIs from Java

Squid Efficiency Analyzer interprets a Squid log (native) for proxy efficiency.