makeself is a small shell script that generates a self-extractable compressed TAR archive from a directory. The resulting file appears as a shell script, and can be launched as is. The archive will then uncompress itself to a temporary directory and an arbitrary command will be executed (for example, an installation script). This is pretty similar to archives generated with WinZip Self-Extractor in the Windows world.
PIKT is cross-categorical, multi-purpose software for monitoring and configuring computer systems, administering networks, organizing system security, and much more. PIKT is intended primarily for system monitoring, and secondarily for configuration management, but its versatility and extensibility evoke many other wide-ranging uses. PIKT consists of a sophisticated, feature-rich file preprocessor; an innovative scripting language with unique labor-saving features; a flexible, centrally directed process scheduler; a customizing file installer; a collection of powerful command-line extensions; and other useful tools.
cvsroot is a script to help keep track of multiple sites when using CVS, and in particular the CVSROOT and CVS_RSH environment variables for those sites. It creates a $HOME/.cvsroot file, with shortcut names representing the different CVS sites. The new environment variables appropriate to the site selected will then be set, and a new shell will be spawned to keep the variables. In this way, you do not have to keep setting the environment yourself, and can rely on the script to keep track of things for you.