DynamicWorkspaces is a small utility designed to dynamically adjust the number of workspaces (some call them virtual desktops) on your desktop. It will create or delete workspaces such that you always have one workspace free. You can also tell the program to keep at least n workspaces, no matter the number of windows opened (for example, to have at least 3 workspaces, plus at least one free). A common use for DynamicWorkspaces is to tell your window manager to launch it when you log in, so you just use it and forget about it.
iloog is a Gentoo-based live CD targeted mainly at students and scientists. It features UnionFS filesystem support that enables you to write everywhere on the LiveCD and install extra packages, a graphical X environment through the Fluxbox window manager, many programming editors and IDEs, and a plethora of scientific applications, including Octave, Namd, Merlin, and full (La)TeX support.
KNOPPIX is a bootable CD with a collection of GNU/Linux software, automatic hardware detection, and support for many graphics cards, sound cards, SCSI devices, and other peripherals. It can be used as a Linux demo, educational CD, rescue system, etc. It is not necessary to install anything on a hard disk due to on-the-fly decompression.
The Virtual Tab Window Manager (VTWM) is a virtual window manager with adjustable graphical complexity. With minimal settings, it is ideal for limited resource situations, using little memory, little CPU time, few colors, and little bandwidth. Fully blown, it supports m4 and regex processing of the resource file, sound effects, user-defined color icons and buttons, and more.
awm is a custom window manager. It's small, functional, and fast. It is based on dwm and is just ~1800 lines of code. It is based on the workspace concept, but the space is two dimensional. Each time you move to a new, unvisited workspace, a terminal window is automatically launched, emulating TTYs' behavior. You can delete an entire workspace, killing all the windows launched in it. You can even delete an entire dimension, deleting all the residing workspaces. To resize a window, you just Alt+RightClick on any point of the screen, and the window will immediately resize. The windows can be ordered on the fly with the tiling algorithm of dwm, and then restored. This is useful to get a quick glimpse of the current workspace. A proc-like interface can be used retrieve information from awm.