@ (monkey-tail) is a simple collection of simple commands. Built-in commands include listing of memory usage and open files for a process (by name or PID), running processes detached from a terminal, and running a program only once. @ can merge external pieces of code into itself to provide extra commands. Additionally, these "externals" can then be updated from their source. Currently there are externals available for extracting archive files (including nested archives), setting the GNOME desktop wallpaper image, and for replicating @ to another host via SSH. Externals can easily be written, as they are simply collections of Bash functions. It is completely self contained and self modifying, and is implemented in a single file.
Rerun is a lightweight tool-building framework useful to those implementing management procedure with shell scripts. It will help you organize your implementation into well-defined modular interfaces. Collections of management modules can be archived and delivered as a single executable to facilitate team handoffs. Using the "stubbs" module, rerun will even facilitate unit tests. When users execute rerun module commands, rerun can record execution data into log files which can later be replayed.
Pipa reads data from stdin and does various things with it: rotates by time interval / output file size; compresses it (gz, bz2, lzo, xz); names the output file with strftime(); splits it intelligently when given info about the file structure (newlines / PCAP); calls a user command on the finished output file; passes it to stdout (like tee); and more.