Since v2.04, bash has allowed you to intelligently program and extend its standard completion behavior to achieve complex command lines with just a few keystrokes. Imagine typing ssh [Tab] and being able to complete on hosts from your ~/.ssh/known_hosts files. Or typing man 3 str [Tab] and getting a list of all string handling functions in the UNIX manual. mount system: [Tab] would complete on all exported file-systems from the host called system, while make [Tab] would complete on all targets in Makefile. This project was conceived to produce programmable completion routines for the most common Linux/UNIX commands, reducing the amount of typing sysadmins and programmers need to do on a daily basis.
Tcsh is an enhanced but completely compatible version of the Berkeley UNIX C shell. It is a command language interpreter usable both as an interactive login shell and a shell script command processor. It includes a command line editor, programmable word completion, command and file name completion, listing, spelling correction, a history mechanism, job control, and a bunch of small additions to the csh shell itself.
GNU Bash is an sh-compatible command language interpreter that executes commands read from the standard input or from a file. Bash also incorporates useful features from the Korn and C shells (ksh and csh). Bash is intended to be a conforming implementation of the IEEE POSIX Shell and Tools specification (IEEE Working Group 1003.2).
execline is a very light, non-interactive scripting language, which is similar to a shell. Simple shell scripts can be easily rewritten in the execline language, improving performance and memory usage. execline was designed for use in embedded systems, but works on most Unix flavors.
fli4l is a single-floppy Linux-based ISDN/DSL/ethernet-router. It features configuration with some simple ASCII-files, several possible connection-flavors (in/out/callback, and raw IP/PPP), channel bundling (an extra channel can be added through a Windows/Unix-client), configuration of multiple networks, least-cost routing, automatic choice of provider, display/calculation of connection times and costs, and a Windows/Unix client to control dial/hangup, monitor traffic and monitor incoming calls on ISDN (see screenshot).
Zenity is a tool that allows you to display Gtk+ dialog boxes from the command line and through shell scripts. It is similar to gdialog, but is intended to be saner. It comes from the same family as dialog, Xdialog, and cdialog, but it surpasses those projects by having a cooler name.
The klish is a framework for implementing Cisco-like command-line interfaces on Unix systems. It is configurable through XML files. "Klish" stands for "Kommand Line Interface SHell". The klish is a fork of clish-0.7.3. The original clish was developed by Graeme McKerrell. The klish adds some new features, but is compatible (as much as possible) with clish's XML configuration files.