Rebel Search is a state-of-the-art search engine for Microsoft SharePoint 2010. Developed from scratch by passionate SharePoint geeks purposefully for the SharePoint platform it is much better than built-in Foundation or SharePoint Server search.
It is a modern product featuring: faceted navigation, powerful query language, high indexing and searching speeds, ease of configuration, great extensibility and more.
It is designed to help your users find valuable information in your document corpus faster and without hassle.
Feature
Benefit
Deep Facet Navigation
It features high-end search user interface with deep faceted refinements,document preview, visual hit count indicators & rich query language. It helps end users find information faster.
Fully Integrated with DataFacet
RebelSearch is built from the ground-up to support taxonomies and faceted navigation. DataFacet provides powerful taxonomy editing and auto-tagging features for SharePoint and external document sources.
Document Preview
View documents quickly in a popup window without having to open the document in an external application.
Real-Time Indexing
It is the only real-time search engine for SharePoint. Every document you upload or modify appears in the search results immediately. No need to wait for a next incremental crawl.
Cost Effective
Licensing benefits. With Rebel Search you could get very powerful search solution running on Foundation. There is no need to buy SharePoint Enterprise CAL’s (like you need for FAST) or even the SharePoint Server License. Depending on number of employees in your organization that could be a huge savings.
Hardware Efficient
Crawling is much faster with Rebel Search. That means you’ll need less hardware to index effectively same number of documents (compared to standard search).
100% Native .Net Code
It is more extensible. No sealed classes. No inherited native code It has an extensible pipeline and is written completely in .Net giving you unmatched liberty to create customized search solutions. Add to that easier & faster.
Easy to Install and Maintain
Installation & maintenance is almost trivial. Carefully chosen configuration defaults and better architecture saves your system administrator from hardcore search issues troubleshooting inherent to built-in search.

AR·Semantics provides automatic tagging, taxonomy management and faceted navigation features to enterprise content management and enterprise search applications.