rvi is a wrapper script which gives you an easy way of integrating RCS with your existing vim/vi work environment. Simply use "rvi filename" instead of "vim filename", and the file will automatically be checked into revision control, and the changes you made after the edit will be displayed each time you finish editing.
aee is a text editor that is intended to be usable with little or no instruction. It provides both a terminal (curses based) interface and native X-Windows interface (in which case the executable is called xae). Features include pop-up menus, journalling (to recover from system crash or loss of connection), cut-and-paste, multiple buffers (associated with files or not), and much more.
Elvis is a clone of vi/ex, the standard UNIX editor. Elvis supports nearly all of the vi/ex commands, in both visual mode and ex mode. Elvis adds support for multiple files, multiple windows, a variety of display modes including "hex" and "html", on-line help, WYSIWYG printing, and other miscellaneous extensions.