“GNU's Not Unix” curves above, and “Free Software Foundation” borders below in this Lisp-like statement about GNU. Two “parentheses” formed by curved, dancing GNUs form a pseudo-Lisp program: (USE 'GNU).
The dancing GNU parentheses were drawn by Etienne Suvasa. They are part of the cover art for the GNU Emacs Lisp Reference manual.
The rest of this art was designed by the FSF staff for the 1996 GNU T-shirt.
This picture is available in the following formats:
Other art in the GNU Art Gallery.