Simple script that toggles visibility of hidden files in OS X. It requires Python 2.7.

vision.py

#!/usr/bin/env python
# vision

import subprocess

output = subprocess.check_output(
        ["defaults", "read", "com.apple.finder", "AppleShowAllFiles"])
if "NO" in output:
    subprocess.call(["defaults", "write", "com.apple.finder", 
                    "AppleShowAllFiles", "YES"])
    subprocess.call(["killall", "Finder"])
    print "Hidden files are now visible."
if "YES" in output:
    subprocess.call(["defaults", "write", "com.apple.finder",
                    "AppleShowAllFiles", "NO"])
    subprocess.call(["killall", "Finder"])
    print "Hidden files are now hidden."