The latest version of NEdit, in my opinion the best program text editor
there is, is supporting calltips: little boxes that pop up on demand
with information about function calls.
"Atoms and Definitions of Joy" is now available in calltips format, too.
http://groups.yahoo.com/group/concatenative/files/rabbit/joy-funs-doc.calltips.txt
-- good glide into 2004
-- Heiko