Arguably the most successful platform whose code can be easily modified at runtime. Emacs presents this through the metaphor of a text editor, though the Emacs platform has been about more than that since pretty much its inception. Emacs as a platform hosts email readers, Usenet clients, web and Gopher browsers, games, terminal emulators, sftp clients, chat clients, and even a window manager. With org-mode, most of these (including the email clients) can be linked together with agendas, task ...
