Tenex C Shell (tcsh)
Great, enhanced, but completely compatible version of the Berkeley UNIX C shell (csh). It is a command language interpreter usable both as an interactive login shell and a shell script command processor which uses C-like syntax. It's what I use by default.
Public Domain Korn Shell (pdksh)
A clone of the AT&T Korn shell. At present, it has most of the ksh88 features, some (not many) of the ksh93 features, and a number of its own features.
The Z Shell (zsh)
Powerful, full-featured, Bourne-compatible, interactive shell and script command processor.
$links directory, v1.1.16, 2011/03/07$