Shell (computing):
$,
console,
terminal
Shell (nature): chaf,
cover, husk, seed
goosh.org >>the unofficial google shell.
Hotwire-Shell.org >>A modern hybrid textual/graphical shell for developers and system administrators
fishShell.org >>fish is a user friendly command line shell for UNIX-like operating systems such as Linux.
Mooix.net >>Mooix is a MOO, an object-oriented multi-user virtual world that users can log into and explore. Each user takes control of a computerized avatar. You can walk around, chat with other people, solve puzzles, and even extend and change the world by creating new places and items and adding your own code.
bourilko.web.cern.ch/bourilko/caves.html >>CAVES: Collaborative Analysis Versioning Environment System CODESH: COllaborative DEvelopment SHell