OfficeWriter for Word from SoftArtisans provides that functionality. OfficeWriter is a Windows server application that starts with your Word Template and then performs variable substitution to create a Word-compliant .doc file (among other formats). And it does so without installing Office or Word on your Windows server. Therefor, OfficeWriter can generate 1,000s of Word files precisely to your requirements in a "lights-out" environment.
Here's an example. Let's say that you need to generate outbound forms that will be filled-in by people who then fax back the documents to you for processing - order forms, registration forms, applications, and the like.
With OfficeWriter, you can create your template form using Word on your desktop, then give OfficeWriter on your serve the template, configure your datasources and merge criteria, and the let it rip! OfficeWriter will create individual .doc files that have been customized with Names, Addresses, Order Quantities, etc. From there, you could hand the .doc files directly to RightFax:
“A new conversion engine converts documents to faxes on the RightFax Server from native applications such as Microsoft Word, PowerPoint, Excel and HTML. The new conversion engine … uses Microsoft .NET APIs to automate Microsoft programs.”
RightFax, in turn, will fax the converted .doc files to the appropriate fax numbers. After people make their corrections, updates, signatures to the faxed documents, they can then fax them back to the RightFax server.
A pretty slick way to begin automating a paper-based, manual process. It's a step in the right direction!