I was just reading my usual 4 or 5 websites that I usually do in the morning, before the obligatory cup of coffee. When I noticed that Microsoft are offering a free plugin for Word 2003.
The Word redaction pluging can be downloaded here.
By using the Word 2003 Redaction Add-in, you can mark sections of Microsoft Office Word 2003 documents for redaction. You can then create a new, redacted version of the document in which this marked text is unavailable.