cfgsh is a configuration shell utility that is intended to be used for configuring embedded systems. It is meant to replace the normal combination of utilities including ifconfig, route, startup scripts, and configuration files with a single program that implements the same functionality in a manner more consistent with the embedded system world.
guard bash is a shell wrapper that will execute an authentication phase before any command is executed. It uses a secret (user owned) algorithm method, and has a per user customizable procedure. If you need to connect to your computer from outside of your safe environment, even if you use SSH, you are vulnerable to simple attacks like key sniffing or to more complex attacks against SSH. If you have more than just one authentication method, you can more safely log in your account from an insecure Internet host.
Zoidberg (a.k.a. zoid) provides a modular Perl shell written, configured, and operated entirely in Perl. It aspires to be a fully operational login shell with all the features one normally expects. But it also gives direct access to Perl objects and data structures from the command line, and allows you to run Perl code within the scope of your command line.
MSYS (Minimal SYStem) provides POSIX/Bourne configure scripts the ability to execute and create a Makefile used by make on Windows systems. This includes a pseudo-terminal, bash, make, sed, awk, etc. Together with a MinGW installation this environment is comparable to a Cygwin installation, except that it is really open source.
Nast is a packet sniffer and a LAN analyzer based on Libnet and Libpcap. It can sniff the packets on a network interface in normal mode or in promiscuous mode. It dumps the headers of packets and the payload in ASCII or ASCII-hex format. Various packet filters can be applied. The data sniffed can be saved in a separate file. As an analysis tool, it can check for other NICs on the network which are set in promiscuous mode, build a list of all hosts on a LAN, find a gateway, perform port scanning on a multiple hosts, catch daemon banners, follow the TCP data stream, reset a connection, and determine whether a link type is a hub or switch.