Batch Docs - Replace text in, add or remove content, and edit thousands of Word documents in doc and docx formats, PDFs, RTF documents, and other text documents.
mat2 - mat2 is a metadata removal tool, supporting a wide range of commonly used file formats.
Multi String Replacer - Replace multiple strings at once!
Attribute Magic - AttributeMagic.com - utility to change file timestamps and metadata
Actual Search And Replace - This is an advanced tool to perform the search and replace operations across multiple text files. It supports the regular expressions syntax. The batch replace operation allows to execute a lot of various replacements with one click.
GroupDocs.Metadata for .NET - GroupDocs.Metadata for .