CitySearch for iPhone
CitySearch a Google Maps mash-up that lets you lookup locations of restaurants, hotels, bars, pubs, nightlife, shopping and services in all major US cities has now been optimised to work with the iPhone. If you don't have an iPhone you can see how it looks on this iPhone simulator.
The conversion works very well on a mobile phone. To search for locations CitySearch uses a series of dropdown menus; you choose a city from the first menu, you then choose whether you are searching for restaurants, shops etc before finally choosing the type of restaurant or shop etc.
The results are then tagged on a Google Map. Clicking on any of the tags opens an information window with the address and a brief description of the location. There is also the option to get driving directions to the venue.