on run
 -- Read the current value of AppleShowAllFiles
 set plistValue to do shell script "defaults read com.apple.finder AppleShowAllFiles"
 set plistCommand to "defaults write com.apple.finder AppleShowAllFiles"

 if plistValue is "false" then
    set shellCommand to plistCommand & " true"
 else
    set shellCommand to plistCommand & " false"
 end if
 do shell script shellCommand

 -- Restart the Finder to see the new value
 do shell script "killall Finder"
end run

on run
 -- Read the current value of AppleShowAllFiles
 set plistValue to do shell script "defaults read com.apple.finder AppleShowAllFiles"
 set plistCommand to "defaults write com.apple.finder AppleShowAllFiles"

 if plistValue is "false" then
    set shellCommand to plistCommand & " true"
 else
    set shellCommand to plistCommand & " false"
 end if
 set results to do shell script shellCommand

 -- Restart the Finder to see the new value
 do shell script "killall Finder"
end run

http://www.cappellin.net/2013/06/visualizzare-i-file-nascosti-in-mac-os-x-108-mountain-lion-e-107-lion.html

This script show/hide the hidden files and folders in your Mac OS X. It works in OS X 10.8 Mountain Lion, but I think it should work in 10.6 and 10.7, too.

Show/Hide Hidden Files in Mac OS X

files

AppleScript