by 
Upgrade your iPod Nano 4G and Touch 2G devices with the ThumbTack ($13) from SwitchEasy. This tiny thumbtack shaped microphone works with third-party applications and connects to the iPod’s 3.5mm headphone jack to deliver outstanding quality sound recording. The ThumbTack is available in red, white and black and features high quality gold-plated non-corrosive plug.