Microsoft is working on a unified search user interface designed to kill Google Desktop and thwart Google’s business software services. Code-named Casino and referred to as OneView, the new application provides one user interface for searching across the desktop, intranets and the Web, according to Microsoft’s Web site. The intent is to crush Google’s efforts in the enterprise intranet and desktop search market and prevent Google from using its leading search engine to push the company deeper into business software services, which the search giant announced Thursday. Several solution providers said the Casino application — similar to Google Desktop — is in beta testing but isn’t ready to ship yet. The application is expected to be integrated with Windows Vista and Windows Live Search.