OS X 10.9

Run:

easy_install PIL

An exception is thrown:

fatal error: 'freetype/fterrors.h' file not found
#include <freetype/fterrors.h>
         ^
1 error generated.
error: Setup script exited with error: command 'clang' failed with exit status 1

fixed:

ln -s /usr/local/include/freetype2 /usr/local/include/freetype