Emacs lolz.

"GNU Emacs is an old-school C program emulating a 1980s Symbolics Lisp Machine emulating an old-fashioned Motif-style Xt toolkit emulating a 1970s text terminal emulating a 1960s teletype. Compiling Emacs is a challenge."

https://www.facebook.com/notes/daniel-colascione/buttery-smooth-emacs/10155313440066102/