Karaoke Anything! is a free Windows program that lets you turn your PC into the ‘ultimate karaoke machine’. Not tried it, so can’t say whether it’s totally kosher. Caveat emptor!
‘Realtime audio processing allows you to remove the vocals from almost any song making it perfect for karaoke!…Karaoke Anything! supports both .mp3 files and regular CD Audio. You can either open an mp3 or simply insert an Audio CD into your CD/DVD drive and you’re ready to go!…Karaoke Anything! uses a vocal removing technique that sums the left channel with the inverse of the right. It then places the results into both channels. We call it the “karaoke effect”‘