ProxyList.com

Proxy Server Info
Proxy server guide and a small list of anonymous proxies.
www.proxy-server.info/

Microsoft Proxy Server
Discontinued extensible firewall and integrated web cache server. Information on migrating to ISA server, service packs and hotfix downloads. [Windows NT Server]
www.microsoft.com/

Proxy Log Analyzer
Software for extracting and analyzing data from MS Proxy Server and ISA server log files. Sample report files and ordering information.
www.mechanicalminds.com/

Netscape Proxy Server
Offers web caching, content filtering, access control and activity reporting. [Unix, Windows]
wp.netscape.com/

Oops! proxy server
Open source web and ftp caching proxy. [Unix, Linux, FreeBSD]
zipper.paco.net/

micro_proxy
HTTP/HTTPS proxy that runs from inetd, and uses less than 1kb of diskspace. [Unix]
www.acme.com/

ftp.proxy
Offers application layer FTP service proxying to facilitate use of service through firewalls. Supports various access control options. [Unix, Linux, BSD, Windows]
www.ftpproxy.org/

Spoon Proxy
Offers connection sharing and logging. [Windows]
www.pi-soft.com/

Apple.com: RTSP/RTP Proxy
Offers client machines within a protected network access to streaming servers outside the firewall. [Mac OS]
developer.apple.com/

EServ
Offers mail and news server hosting, web caching and activity logging. Trial downloads, online ordering and PDF documentation. [Windows]
www.eserv.ru/