The 64 Studio Platform Development Kit (PDK) is a version control system for GNU/Linux distributions, allowing the creation and management of many different projects, based on Debian and Ubuntu sources. PDK is written in Python, and the source code is well commented and contains documented examples.
Nexenta is a complete GNU-based operating system built on top of the OpenSolaris kernel and runtime. The Debian system is used for software distribution and packaging to glue the numerous pieces together. However, Nexenta is not currently part of the Debian Project, nor are its packages present in the Debian database. It includes Apache, MySQL, Perl, Python, PHP, Firefox, Evolution, a software update manager, Synaptic package manager, Gaim, Abiword, administration and development utilities, editors, graphics, GNOME, interpreters, libraries, and much more.
flashboot for OpenBSD is a set of makefiles, scripts, and support tools to build an OpenBSD image suitable for booting from read-only media, such as flash memory. The default image (smaller than 5Mb) is an image for a firewall/router with support for IPsec, SSH, IPv4 and IPv6 packet filtering, DHCP (client and server), and PPPoE. This image may be further trimmed or extended by editing the packing list files included in the distribution.