Many (many) years ago in the age of MS-DOS when Unix on the PC was still a dream, there was an editor called Brief. It was far and away the best editor available for DOS. It was fast, had multiple windows, regular expression search and replace, multiple undo/redo, could deal with rectangular regions, and could even call and interact with your compiler directly from the editor.
It was, in short, very Emacs-like and even had a Lisp extension language. Later, they added a C-like extension language. I recall the developers saying that it was inspired by Emacs. For example, a lot of the editor was implemented in the extension language(s). Of course, it wasn’t as powerful as Emacs: you couldn’t do things like listen to music with it or any of the many other things that we do from within Emacs but it was a darn good editor and had a fanatical following.
I remember it fondly and regret that it died with DOS (although there were OS/2 and Window versions). It turns out, though, that it hasn’t quite died. One of those fanatical followers, Luke Lee, has been working on emulating it under Emacs for over 17 years. Now, finally, he feels that it’s ready for official release.
There probably aren’t a lot of people who still have Brief muscle memory or who would prefer the Brief emulation to normal Emacs but if you are such a person, Lee has just added it to the ELPA package master branch. Lee’s announcement on emacs-devel is detailed and describes the changes and enhancements he made. If you were a Brief user and would like to relive the old days, give it a try.