Siri is a FREE app for the iPhone 3GS that uses voice recognition to find what you're looking for quickly without the hassle of searching the web on your own. You tell Siri what you’re looking for and it searches the web and gives you the results in seconds. Just like a real assistant, Siri understands what you say, accomplishes tasks for you and adapts to your preferences over time. Siri can book restaurants, movies, events, help you find local businesses, call a cab and check the weather.
They are working on bringing Siri to the iPhone 3G, iPod Touch, iPad, Blackberry and Android devices as well so be looking out for an update soon.