There happened to be some discussion on this on
comp.emacs and the relevant upshot is: Here's a project
for someone who wouldn't mind gaining the undying
adulation of the Lisp/Scheme community: A Lisp or
Scheme mode for JED Emacs.
(JED is a fast and small Emacs-like editor by John
E. Davis that has an extension language and that is
commonly used on PCs that would wilt under Gnu Emacs.
JED is available from amy.tch.harvard.edu.)
--d