Converts encrypted Adobe product keys found in the registry to keys used to install.  Useful when refreshing a PC to find the key used to install the software on the old computer.  In my experience so far this has worked with all Adobe products I've tested.
The encrypted key is usually located under HKLM\Software\Adobe\{Product}\{Version}\Registration
Second place to check would be HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall\{GUID}
An update, I initially had this saved so that it created a function "ConvertFrom-EncryptedAdobeKey", I've updated it now so it functions as a script first.  If you want to use it as a function, just uncomment the first and last lines.  With it as is, you can now just save the script from technet and call it with the parameters (encrypted key) just after the call.
#function ConvertFrom-EncryptedAdobeKey { 
        [Parameter(Position=0, Mandatory=$true)]  
    $AdobeCipher = "0000000001""5038647192""1456053789""2604371895", 
    $counter = 0 
    $DecryptedKey = "" 
    While ($counter -ne 24) { 
        $DecryptedKey +$AdobeCipher[$counter].substring($EncryptedKey.SubString($counter, 1), 1) 
        $counter ++ 
#    Converts encrypted key for adobe products to decrypted key used to install application. 
#    Converts encrypted key for adobe products to decrypted key used to install application. 
#    The encrypted key can be found in the registry under the Local Machine hive, under software, adobe,  
#    then the product you are looking for (IE, Acrobat), the version you are looking for (IE. 7.0), 
#    then the Registration key.  Just copy from there and paste as the input for the function. 
#    .PARAMETER EncryptedKey 
#    The encrypted version of the adobe key found in the registry. 
#    .OUTPUTS 
#    System.String. Returns the decrypted key in a string object. 
#    .EXAMPLE 
#    C:\PS> ConvertFrom-EncryptedAdobeKey.ps1 123456789012345678901234 
#    036392546015404819372237