Glk: An I/O library used to make interpreters more portable. You need this if your interpreter says it requires Glk.
Gnusto: Z-machine interpreter for Mozilla
Jzip Development: Open Source Z-code interpreter for UNIX, DOS, OS/2, Atari ST and other machines.
Kwest: A Z-machine interpreter for KDE.
Malyon: A Z-Machine interpreter for GNU Emacs. May be useful combined with the Emacs Inform major mode.
Nitfol: An interpreter intended for debugging. Includes auto-map feature, and debugging (cheat) verbs. Requires Glk for I/O.
Revenge of the Z-Machine: A z-machine interpreter in Java.
Viola: An interpreter written in Python.
Yahoo Groups: ZBurin-IF: A group for discussion of the upcoming ZBurin interactive fiction game playing system for the Cybiko handheld computer.
Yazi: Z-Machine interpereter for the Apple Newton PDA. Shareware. ($25)
Z9K: Z-code Interpreter for the Nokia Communicator.
ZBurin for Cybiko: Preliminary screenshots of a z-code interpreter for the Cybiko.
ZipCE: A Z machine interpreter for Windows CE.
Zoom: ZMachine for UNIX and XWindows or MS Windows.