Usability 
DexKnows is a local search engine listing U.S. restaurants, transportation, entertainment and shopping. It's from R. H. Donnelley, a major publisher of print telephone directories. It's very complete listing 100 Sushi places in San Francisco. Unfortunately results are metro wide making it poorly suited for finding the nearest one. Listings include click to call numbers, maps and directions. There's also a white pages based people search and a reverse phone directory.