This Media Player

NewEgg.com has the Griffin Technology iKaraoke iPod Microphone for $20 + $5 shipping = $25 shipped.

Product description from NewEgg.com:

The iKaraoke is a brilliant business tool, as well as a really fun toy! The all-in-one microphone/processor/FM transmitter connects to your iPod’s docking port, isolates the lead vocal track, and fades it, to make room for your voice. The unit transmits the music and your voice to your home stereo, car stereo, or boom box. You can adjust the volume of the background music, or mute it to use iKaraoke as a PA system! The unit also features controls for scan, skip, and adjustable reverb, so all the control is right in your hand. Whether you want to share your singing skills, or !
kick your next business or trade show presentation up a notch, iKaraoke has something for everyone!

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