Emacs
Emacs is an actively developed open source text editor for code and prose old enough to have heirloom configuration files.1)
It has it's own wiki and stack exchange
Emacs advocates point to the lindy effect 2) and GNU community roots to argue Emacs is a safe investment. While, detractors point to the need for investing time to learn as a reason to avoid Emacs.
evil-mode
for excellent vim emulation (modal editing povides a command grammar of editing)dokuwiki-mode
(see Emacs for wiki editing) for editing this wiki!