Official Google Voice Application on Android PhoneGoogle Voice application now available in the Android Market for Android phone (Tmobile my Touch) users,and Blackberry users can download form m.google.com/voice.With Google voice you can manage your voicemail,call history and Place call that display your Google voice number from your address book and etc.
Here is Google Voice Official Video.
Google Listen App for Android Phone
Visual VoiceMail for Android Phone Users
AppPack for my Touch 3G