PlumpOS is a bootable openMosix node on a CD. Pop the CD into a 486+ computer and you have an instant openMosix node. It supports loading 3rd-party packages and adding custom kernels. It takes up very few resources. It was originally a clone of clump/os, but has evolved into something that doesn't resemble it much anymore.
Rocks is a complete "cluster on a CD" solution for x86 and IA64 Red Hat Linux COTS clusters. Building a Rocks cluster does not require any experience in clustering, yet a cluster architect will find a flexible and programmatic way to redesign the entire software stack just below the surface (appropriately hidden from the majority of users). Although Rocks includes the tools expected from any clustering software stack (PBS, Maui, GM support, Ganglia, etc), it is unique in its simplicity of installation.
Linux4Geeks is a LFS-based small distro which works around several problems and issues mainstream Linux distributions have. It offers different versions compiled for each architecture and has all the packages required for a slim installation including a firewall and network administration tools, amongst others.
Thinux is a thin-client server on a live CD. It boots a network of diskless computers to automatically start an application such as a Web browser. Each thin client machine acts as a cluster node to share its processing and memory resources with each other to take the load off the server. It is a turnkey solution that does not change nor rely on your existing systems to run. By booting from a removable CD, it does not lock-in the user so it is convenient to test. It is ideal for any organizations that require large deployment of software automatically and cost effectively.
m23 is a software deployment system for Debian GNU/Linux that allows you to install and administrate hundreds of clients via network. It can partition and format clients and install Debian, (K/X)Ubuntu, Linux Mint, Fedora, OpenSuse, and CentOS operating systems on your virtual and physical clients. Group functions allow the comfortable update and installation of further packages during operation. Mass installation functions simplify your administration chores. m23 has a Web interface. Backup functions are implemented for server and clients.
redWall is a bootable CD-ROM firewall which focuses on Web-based reporting of the firewall's status. It includes Snort, snortsam, dansguardian, and support for fwbuilder, squidguard, reporting (using BASE/sarg/ntop/webfwlog), VPN (Openswan/PoPToP/Openvpn), Spam Filtering (spamassassin, dcc, razor2, clamav, amavis-new, dspam and maia mailguard), and mail-based, alerting. Configuration data are stored on a floppy or USB disk.
OpenVPS is a set of software built on top of the Linux VServer aimed specifically at Web Hosting. It is not another set of kernel patches, but a set of scripts to create virtual servers, collect resource utilization information, and provide an interface to the customer as well as the administrator.
Instant-Grid is a Knoppix-based live-CD bundled with a pre-configured grid environment based on the Globus Toolkit. One PC started from this CD becomes the Instant-Grid frontend. It also functions as a PXE boot-server, allowing other PCs in the same local network to boot the Instant-Grid environment. Together with the frontend, these PCs automatically form a working test grid. Like with the original Knoppix, the existing configuration of the participating PC is not touched (except maybe for enabling the PXE boot-option), and remains instantly available by a simple reboot.
footprint is a tool that makes it easier to create and manage kickstart files. It allows you to define systems, create profiles for systems, and macros per distribution. It can create kickstart files on the fly, make custom initrd (ramdisks), create custom bootfloppies, and can manage your DHCP and PXE configuration.