An emacs minor mode for showing the current scope in Lisp-like languages.
parscope-mode highlights the current scope by creating an overlay with parscope-overlay-face that extends to cover the body of the current S-expression. As you might imagine, this works pretty well in Lisp-like languages (Common Lisp, Emacs Lisp, Clojure, etc) and even works somewhat-well for Algol-based languages.
Installation is simple - either install it from Marmalade, or copy the file to your load path and add this to your init file:
(require 'parscope)
To enable parscope for the current buffer, use M-x parscope-mode. parscope will automatically highlight the current S-expression's scope. Customize the appearance of the overlay by tweaking parscope-overlay-face.