DSL is a very versatile 50MB mini desktop oriented Linux distribution.
Damn Small is small enough and smart enough to do the following things: 
  Boot from a business card CD as a live linux distribution (LiveCD) 
  Boot from a USB drive 
  Boot from within a host operating system (that's right, it can run "inside" 
  Windows) 
  Run very nicely from an IDE Compact Flash drive via a method we call "frugal 
  install" 
  Transform into a Debian OS with a traditional hard drive install 
  Run light enough to power a 486DX with 16MB of Ram 
  Run fully in RAM with as little as 128MB (you will be amazed at how fast your 
  computer can be!) 
  Modularly grow -- DSL is highly extendable without the need to customize 
  DSL was originally developed as an experiment to see how many usable desktop 
  applications can fit inside a 50MB live CD. It was at first just a personal 
  tool/toy. But over time Damn Small Linux grew into a community project with 
  hundreds of development hours put into refinements including a fully automated 
  remote and local application installation system and a very versatile backup 
  and restore system which may be used with any writable media including a hard 
  drive, a floppy drive, or a USB device.
  DSL has a nearly complete desktop, and many command line tools. All applications 
  are chosen with the best balance of functionality, size and speed. Damn Small 
  also has the ability to act as an SSH/FTP/HTTPD server right off of a live CD. 
  In our quest to save space and have a fully functional desktop we've made many 
  GUI administration tools which are fast yet still easy to use.