Guile

GNU Guile
Growing article, with links to many related topics. [Wikipedia]
http://en.wikipedia.org/wiki/GNU_Guile

Guile
GNU's Ubiquitous Intelligent Language for Extension, a library implementation of the Scheme language plus various convenient facilities. Designed to be linked into programs to make them extensible.
http://www.gnu.org/software/guile/guile.html

Guile Object Oriented Programming System: GOOPS
Object-oriented extension to Guile; very close in spirit to Common Lisp Object System, CLOS (CLtL2), but adapted for Scheme language; gives full OO system with multiple inheritance, generic functions with multi-method dispatch.
http://www.gnu.org/software/goops/goops.html

guile-gtk
Guile bindings for Gtk+.
http://www.gnu.org/software/guile-gtk/

guile-gtk-general
Maillist for general discussions about the guile-gtk project.
http://lists.gnu.org/mailman/listinfo/guile-gtk-general/