A version of DSL is available bundled with the freeware QEMU virtualizer; QEMU is roughly comparable to VMware, though QEMU can also emulate different processors. This bundle, called DSL embedded, can be unpacked into a subdirectory and run in Windows immediately. This can be done with other Linuxes, but DSL embedded puts all the pieces together for you. It's a fine way to experiment with DSL without having to burn a CD or download and configure a virtual PC system.
The builders of DSL wanted to create a nomadic environment, one not bound to a particular machine's hardware configuration but easily adjusted to whatever hardware configuration it found itself in. They have succeeded well.
Linux for older hardware
Suppose you have an elderly, early-Pentium PC sitting unused under a desk. Being environmentally conscious, you want to put it to use, perhaps as a Web-browsing station, a simple word processor, or running an in-house Web server. But you don't want an OS that exceeds the hardware's capabilities.
Fortunately, there are Linux distributions specifically targeted to older hardware. Two examples are antiX Linux and SliTaz Linux.
antiX Linux has a boot-image footprint that's roughly 400MB in size. Based on MEPIS Linux, antiX was created by MEPIS community member Paul Banham, known in the MEPIS community as "anticapitalista." MEPIS is a popular Linux distribution; antiX is not an official MEPIS project.
Banham chose MEPIS for antiX because he'd been working with MEPIS for about four years and found the MEPIS core -- kernel, MEPIS tools, and the MEPIS installer -- to be a "great base for new and experienced Linux users." His small Linux is aimed at systems with about 128MB of RAM. It can run in as little as 64MB; however, in that space, it will need a 128MB swap on the hard drive, and there will be a noticeable loss in performance. You can, of course, run antiX as a LiveCD.
antiX's window manager is Fluxbox, and the system desktop is downright Spartan. There's a minimal status bar at the bottom, and you right-click the desktop for the menu. antiX provides its own control center, from which you can install printers, modify screen resolutions, mount USB devices, set up users, and more. It also provides a link to the Synaptic package-management system.