I am currently evaluating full text search engines for a project that uses Oracle as the back-end db. The basic need is to have all the data (including, but not limited to, HTML files, office docs and PDFs) indexed and then to present an interface or API to query it. I haven't heard any specifics in regards to speed yet, but obviously the faster the better. I know that Sphinx and Oracle Text have been used in the past (I've personally never used either), but new blood is desired. I've used Google Desktop before, but wasn't crazy about it. I've read a little about OSS Open Search Server and it seems to be worth a second look. Has anyone worked with any of these or recommend any others?