Alex's Firewall ByPasser
Alex's Firewall ByPasser is another TCP tunnel for HTTP proxies. It have been tested for MSN Messenger, emule, bittorrent, ftp(passive only), yahoo messenger, irc(xchat) and firefox on Fedora Core 3, FreeBSD 6.0 and MacOS X but should work under all POSIX complaint systems and all proxies allowing https CONNECT.
corkscrew is a simple tool to tunnel TCP connections through an HTTP proxy supporting the CONNECT method. It reads stdin and writes to stdout during the connection, just like netcat.
HTTunnel is a universal HTTP tunnel using Apache, mod_perl and Perl.
Jumpgate is a TCP connection forwarder that provides many enhancements and improvements over the existing programs that do the same thing. It provides an interactive mode that queries the connected party for the forwarding information it needs. Also, there is the option to log the entire forwarded session in a file for later inspection.
Reverse Shell is a tool to create Secure/Remote shell tunnel and then start commands/shells on tunnel destination machine to be executed on tunnel originating machine.
Shell Tunnel provides a normal shell with port forwarding features like those provided by the -L and -R options in ssh. It was written to support a network that uses compile farms. It contains a small application to help to distinguish streams running tests.
Socketpipe directly connects the input/output of a remote process with local programs over a TCP/IP socket. Although the initial communication setup is performed through client-server intermediaries such as SSH or RSH, the communication channel that socketpipe establishes is a direct socket connection between the local and the remote processes, similar to a local pipe.
taptunnel is a TCP/IP-application, which allows to create ethernet-tunnels over the Internet or any other TCP/IP-net.
TunnelTools is a set of Perl scripts to allow access to anonymous rsync and CVS pserver servers from inside a firewall by tunneling over an SSH connection to a machine outside the firewall.
unix2tcp listens on a local UNIX socket and tunnel any incoming connections and traffic to a (remote) IP address/port.
Very Strange Tunneling Tool
VSTT is a multi-protocol tunneling tool. It accepts input by TCP stream sockets and FIFOs, and can send data via TCP, POP3, and ICMP tunneling.
Virtual Private Ethernet
Virtual Private Ethernet creates a virtual ethernet (broadcasts supported, any protocol that works with a normal ethernet should work with VPE) by creating host-to-host tunnels between multiple endpoints.
xhopper is a simple port forwarding tool that was designed to be simple and portable, especially to old machines. It includes some features for getting access to machines that are not directly accessible.