There is a clone for X-windows called "Wily" (http://www.cse.yorku.ca/~oz/wily/). I'm not sure if it is still actively developed -- the website hasn't changed much since the 90's. I used it for a while as my editor in the mid-90's. I liked the tiling window placement and the extensibility model: instead of building new functionality in an extension language (e.g. Emacs Lisp), you build it in external programs which interact via an RPC protocol. The biggest drawback is that you really need a 3-button mouse to effectively use Wily/Acme. Mouse-chords are to Acme/Wily as the control key is to Emacs.