If you own a Google Android based T-Mobile G1 phone, you can now start searching and web surfing with your voice. The upcoming Android update will bring this feature integrated in the Android browser and the home screen search widget, anoounced GoogleMobile blog.
How to use it: On the home screen search widget, look for the microphone button right next to the search box and the search button. Press that button, wait for the "Speak now" prompt, and then say your query. You'll soon see search results formatted for the Android browser. Also, whenever you're in the Android browser, just press the "Menu" button and tap "Search". You'll see the same microphone button there too.
Note that you can use the "Voice Dialer" app, which you can find on the main app menu, to search for your contacts with your voice to make a call. Or, simply long-press the green call button and follow the prompts on the splash screen.
Finally, if your speech is not interpreted correctly, try tapping the down arrow to the right of the search box and you'll see a drop down list of other suggested queries. Look for your query there.