In Emacs on Mac OSX, is there a function to reveal the current file in the Finder?
A bit late, but I just created a script based on this. When invoked from a dired buffer, it opens the folder.
https://github.com/kaz-yos/reveal-in-osx-finder (new link)
EDIT 2014-02-06 Now available on MELPA: M-x list-packages should list reveal-in-finder among other packages.
See here for use. https://github.com/kaz-yos/reveal-in-osx-finder
EDIT 2014-04-08 I slightly updated the script (below). This should be helpful in a dired buffer.
(NEW in 0.3.0) If M-x reveal-in-finder is invoked in a dired buffer, it will open the current folder in the OS X Finder. It will also highlight the file at point if available.
EDIT 2015-08-03 The package was renamed to reveal-in-osx-finder.el to avoid possible confusion with other kinds of "finders".