I am not sure there are any open source alternatives available for the G4 hardware. Cross-platform opensource compiling was nearly impossible on the G4 hardware. It was really the intel hardware that brought Mac OSX into the mainstream FOSS environment. You could install Linux on your powerbook and run Mixxx for Linux. Of course beware that I WILL ALWAYS recomment Linux here :-)
Not Sure..
I am not sure there are any open source alternatives available for the G4 hardware. Cross-platform opensource compiling was nearly impossible on the G4 hardware. It was really the intel hardware that brought Mac OSX into the mainstream FOSS environment. You could install Linux on your powerbook and run Mixxx for Linux. Of course beware that I WILL ALWAYS recomment Linux here :-)