PDF files have various Open Parameter options: you can link to a PDF at a specific page, named destination, zoom level, etc. You can even use a FDF file to populate form data, but this requires having such a file available on your server. It's easier to just do it directly from the URL, which is where this script comes into play.

With this new script created by me you can create a hyperlink to a PDF file, which will also populate it with some pre-defined values, using a simple URL parameter, like so:
http://www.myserver.com/files/products.pdf?rawdata=firstname:John;lastname:Smith
When the reader opens the file in their browser using this link, the form fields ("firstname" and "lastname", in this case) will automatically be populated with the data in the URL ("John" and "Smith", resp.).

IMPORTANT: The script will only work if the file is opened inside the browser window and using the Adobe PDF plugin.

Using the batch version of this script you can apply the code to multiple files in the same process (if you have Acrobat Pro, of course).