Direct purchase using PayPal! ($50 per license)
Update: There's now a free demo version of this tool available. It will process up to 3 items from the list, and create up to 3 tooltips for each item. You can use it to see how the tool works before purchasing the full version.
Do you want the improve your PDF with tooltips (textual popups) that provide additional information for certain words when the reader hovers above them with the mouse? That can be easily achieved with this script.
With this script you can import a list of words or phrases from a text file or Excel spreadsheet, and it will automatically create the tooltip text you defined for each instance of those words or phrases in your file.
There's also a batch version of this script which allows you to add this functionality to multiple files in a single process.
You can download a sample PDF file showing the results of running the tool (also includes the list used in the process), from here.
Update: This script now includes a Batch Process (or Action) that allows you to run it on multiple files. (Requires Acrobat Pro)
For more information about this tool, you can contact me directly.