Local Business Center
If your wish to promote a business, or just would like everyone to know your street address when they search for you name, you can inform Google on this page. Once Google will have verified the infos, your entry will show up on google maps among basic information on your business. On top of the business name, Google lets you display opening hours, phone numers, and main services.


Google Maps API
Google maps lets you use their mapping services to feature an calculate different things. You can think of a store-locator or any other more creative ideas like Paul Neave's Flashearth. As another example, Montreal's public bike service (Bixi) uses it to feature where it's possible to pickup and leave bike in real-time. If you're considering building a map-based component, be sure to checkout the Yahoo Maps Api as well. If you need more customization over you maps and are willing to spend more develpment time, there's many other options available to you. The A-List-Apart website has an exellent article about maps server.