http://www.dtsearch.com/
Instantly Search Terabytes of Text
The dtSearch product line can instantly search terabytes of text across a desktop, network, Internet or Intranet site.
dtSearch products also serve as tools for publishing, with instant text searching, large document collections to Web sites or CD/DVDs.
over two dozen indexed, unindexed, fielded and full-text search options
highlights hits in HTML, XML and PDF while displaying embedded links, formatting and images
converts other file types — word processor, database, spreadsheet, email and full-text of email attachments, ZIP, Unicode, etc. — to HTML for display with highlighted hits
built-in Spider adds local or remote web sites (including dynamically-generated content) to your searchable database