Jia Chengs.
The best part of the whole strange experience of this korean karaoke suggested by John Ko and Stephen Daniels on the 5th hour of 2008 was the constant fear of getting kicked out from all of the breaking of microphones, standing on the tables and screen thing, throwing the light-up tambourine and yelling obscenities.
I use Musicmorpher. It's not free, but if all you want to do is chipmunk songs, and convert song format, then use the trial version. After 7 days it only takes away the major features. pitch is not considered a major feature.