How bind "Super" key *all by itself* to a function?

[Chris Seberino <cseberino@gmail.com>]

I'm on a Linux machine and would like to bind
the "Super" key all by itself to a function of my choosing.

This works for Super + "b":

(global-set-key (kbd "s-b") 'backward-word) 
(Source: http://ergoemacs.org/emacs/emacs_hyper_super_keys.html)

However, how would you do something similar for ONLY the Super key
ALL BY ITSELF???

I tried (global-set-key (kbd "s") 'backward-word)
but then all I'm doing is rebinding the literal "s" which isn't my intention.

(I want to bind another function besides backward-word but that's just a
hypothetical example.)

(I asked a similar question on a list regarding the converting the Windows key to a meta key which led to special problems I'm hoping to avoid now by NOT trying to make Super a meta key.)


cs