Describes many questions encountered when designing faceted search including whether to show dead-ends, options to broaden the search, hierarchies and sub-categories, ranges vs. discrete choices, etc. The screenshot examples are particularly useful.
Greg Notess, a librarian and search engine expert, surveys the new research discovery services (not litigation discovery) from ProQuest, Ex Libris, OCLC, and EBSCO. These are aggregating indexes that attempt to provide Google-style access across library collections and licensed databases. His personal experiences with ProQuest Summon were mixed at best.
Google changed the search API fairly radically, so this is is an interface between the old AJAX version and the new more RESTful version. I'm not sure if it can call the web search engine, now that the API is deprecated. (FWIW, I found the old interface opaque and baffling, will see how the new one works out).