[wicket232]

[Indeed](http://www.emacswiki.org/emacs/EmacsImplementations). And [this](http://en.wikipedia.org/wiki/Emacs#Other_forks_and_clones).

That said, I wonder about the possibility of taking an Emacs written in some other language and adding an Elisp interpreter to it such that it could make use of all the existing Emacs elisp out there.