ZoomSearch

I'm sure they will not mind me pasting this from their site.

• Search results sorted by relevance or by date
• Wildcard searching (eg. "zo?m", "*zoom*")
• Exact phrase searching*
• "Google-like" context search results*
• Highlight words found in search results
• Provide spelling suggestions* and synonyms
• Exclusion/negative searches
• V6 Search Ranking Algorithm and Stemming*
• Display images or thumbnails alongside search results (more)
• Provide recommended links for certain keywords or phrases (more)
• Perform database-like multi-criteria searches using  Custom Meta Fields.
• Capable of serving up to 300 queries per minute
• Can index and search 1000s of web site domains in a single index#
• Search inside DOC, PDF, PPT, XLS, RTF, and WPD files (see plugins#).
• Search a Flash-based site. Index SWF and FlashPaper files (see plugin#).
• A9 and OpenSearch compatible XML/RSS output (CGI only)
• Log all searches made on your website and generate detailed pie-charts and graphical statistic reports* so you know what   your visitors are looking for
• Completely customizable search page appearance with HTML and CSS templates
• International language support (various   charset support, UTF-8, accent, diacritic and ligature options, translated   search pages and more)

See www.grainge.org for RoboHelp and Authoring tips

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