Prometeo is a modular, extensible proxy. It comes with HTTP, FTP (with SSL support), POP3, SSL, and SOCKS 5 modules. Modules can be added or removed at runtime and everything can be configured through a Web interface.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.
The new release of prometeo contains several changes to the HTTP
module. In particular, stability has been improved and filters to
block popups and browser resizing have been implemented.