MUD Shell is a shell that makes the command line very similar to that of a MUD or single player text adventure. To move files, you pick them up like objects, "take xf86config" then move to another directory, "go north" then drop the file, "drop xf86config". The original idea came from a /. post, in which one user discussed the idea of a smart command line that could understand psuedo human speech. This post was later responded to with jokes referencing Zork, a text adventure game with an advanced text interpreter. This in turn, inspired MUD Shell.
You can download and view example usage at: