First post, by Davros
FreeDOS is a complete, free, DOS-compatible operating system that you can use to play classic DOS games, run business software, or develop embedded systems. Any program that works on MS-DOS should also run on FreeDOS.
FreeDOS founder Jim Hall created this handy cheat sheet of useful FreeDOS commands, including an introduction to DOS batch scripts.
Guardian of the Sacred Five Terabyte's of Gaming Goodness