Microsoft has announced Search Server 2008, a search engine based on SharePoint Server and SQL Server.
There are two editions, a free Express version and a paid for variant (price not yet determined) which supports high availability and load balancing on a server farm.
They will be released in the first half of 2008, and a preview release is available immediately here. Both editions require either Windows Server 2003 or the forthcoming Windows Server 2008. A dedicated machine is not required, though it is recommended for best performance.
Search Server can draw results from a variety of sources, including simple file shares, Lotus Notes databases, and search engines such as Wikipedia that support the Open Search standard. There are also providers for Google and Windows Live, and connectors for FileNET and Documentum.
Download: Microsoft Search Server Express RC (x86 and x64 available)
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